Technical Support Resources

TCS Technical Support

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Advanced Consisting (Using CV19)

Question: My consisted (MU'd) engines all blow their horns and ring bells at the same time regardless of what unit is leading. What gives?

If you used your command station to set up the consist and NOT the decoders and CV19, this is expected operation, even if it is not desired. When using a command station to set up a consist, it often won't let you control a locomotive individually and instead always re-directs you to the whole consist.
When doing advanced consisting using CV19 and NOT the command station-based system, the decoders will respond on TWO addresses.

  1. The Base Address (as programmed to either short or long)
  2. The Consist Address as programmed in CV19

On Address 1, all of the sound and light functions will respond all of the time on THAT decoder only. No decoder with a non-zero value in CV19 will respond to speed commands on their base address.
On Address 2, ALL of the engines on that consist address will respond to functions as programmed in CV21 and CV22. Speed commands must be sent on this address.

TCS' preferred recommendation and use case is to:

  • Save your non-consisted settings to a User Preset. (Sound Decoders Only!)
  • Set up the each of the DECODERS in your MU to manage the consist using CV19.
  • Set up individual decoders Consist Function Response using CV21 and CV22 if desired. (This step is optional.)
  • Save these new settings to a different User Preset. (Now you can instantly switch profiles without needing to program anything!)
  • Use the decoders' base addresses for functions like the light, horn, and bell (on the lead unit)
  • Use the consist address for speed control, brakes, muting, etc.

CV19, CV21, and CV22 are covered in-depth in the Comprehensive Programming Guide.

Tony's Train Xchange put together a helpful resource called the Complete Guide To Consisting that you may find quite enlightening.

DC/DCC Operation

Question: Will my DCC decoder run on DC power?

Yes! All TCS decoders are capable of operating on DC track power. This configuration is enabled by default on all non-sound TCS decoders. CV29 can be modified to enable or disable DC operation on any TCS decoder.

Question: Why is my WOWSound locomotive not operating sound functions on DC?

With the exception of OEM decoders/projects such as the Bachmann ACS-64 and Streamlined K4, current and previous version WOWSound decoders do not feature DC sound operation.

Question: Can I program lighting effects on DC?

While it is not possible to perform CV programming or Audio Assist programming on DC, any configurations set on DCC will carry over to DC. For example, if your engine has been programmed to operate a Mars light, firebox flicker, or directional lighting, those settings will carry over into DC operation and behave as if on DCC.

Question: My DC motor/lighting is reversed but it works fine on DCC. Why?

On DCC, the track power is AC with encoded data and as such is not polarized. Due to this, the engine and decoder are only aware of what direction they are/should be going based on the information sent by the command station. Therefore, "forward" is merely a perspective. Conversely, on DC, the track power is polarized. TCS decoders detect the (+) track power rail and base the direction of the motor and lighting depending on which rail is positive. If the track power leads (Red and Black) or motor leads (Orange and Grey) are not going to their respective sides of the locomotive, the decoder's interpretation/assumption of polarity is backwards of reality and should be fixed. Make 100% sure your wires are connected properly if you plan to run on DC frequently or exclusively.

Decoder Resets

Question: My decoder is acting erratically/My decoder won't respond - How do I reset my TCS decoder to factory settings?

Factory resets on ALL TCS decoders are performed by programming CV8 with a value of 2.

NOTE: CV8 is what the NMRA defines to be a "Read Only" CV. What this means is that no value an be used to overwrite the value in this CV; however, TCS has defined several "macros," or sequences of operations which will be performed in the even specific vales are attempted to be programmed. For example, by programming a value of 8, a factory reset will be performed.

On TCS WOWSound decoders, a "nuclear reset" can be performed by programming the following CV's:
CV201 = 5
CV202 = 0
CV203 = 0
CV204 = 8

A nuclear reset will change 100% of the configurations of the decoder. Due to time constraints in certain circumstances, a standard factory reset has been designed to ignore certain CV's and settings. The reset above will load User Preset 1, thereby overwriting everything. If no configurations were previously saved to User Preset 1, the decoder will be loaded will all default settings.

In some situations, a full reset may not be necessary. If for example the issue(s) began after changing the decoder address, it is likely no other problems exist. To reset your decoder address only, ensure CV19 = 0, then Program CV1 to 3 on a Programming Track. Programming tracks ignore addresses and are the only way to resolve address issues.

Decoder Documentation and the Documents Tab

Question: Where can I find programming guides and documents for my TCS product?

An expanded explanation of CV29, as well as other features of your decoder can be found in our online programming guides. By searching your product on our website, you can visit the "Documents" tab to see all of the related literature, documentation, and programming guides for your decoder.

When visiting any product on our website, just click the "Documents" tab on the product page. On this page, you will see a list of links to all of the relevant documentations for that particular item. For example, a sound decoder will have:

  1. Basic decoder literature
  2. The Comprehensive Programming Guide
  3. The Complete Sound Guide for that sound type (Steam/Diesel)
  4. The full list of sounds for all individual Versions
  5. The Audio Assist tree diagram for that sound type (Steam/Diesel Current production version only)
  6. The 4-CV Guided programming tool for that sound type (Steam/Diesel)

Decoder Selection - WOW101 vs. WOW121

Question: What is the difference between a WOW101 and a WOW121?

WOW101 and WOW121 decoders are identical in practical application, meaning they are both capable of providing the same power output, same sounds, and same motor and lighting characteristics. The fundamental difference between them is that the WOW121 relies on a 21-pin motherboard to interface with a locomotive. If you are someone who is planning to 'update' a DC-only model to DCC, there are a few factors to consider:

  • Does this locomotive have a mounting solution for a motherboard, such as a clip or flat surface above the motor?
    • WOW101 decoders are intended as direct plug or hard-wire installations. If the locomotive features a mounting solution for a motherboard, that option is preferable.
  • If I use a motherboard, will there be enough clearance to put the shell back on?
    • TCS decoders fortunately feature an industry-leading low-profile design, and as such can fit into lower shells and tighter spaces much more easily. If width is a concern and a motherboard will not fit, WOW101 decoders are slightly narrower and may be preferable.
  • Do I need to re-motor?
    • If you need to replace your existing drivetrain with a newer or upgraded drivetrain, that system may have a mounting solution. See Point 1.
  • Would it be easier to wire my components directly?
    • Some times it's easier to just run wires directly to the pickups for track, motor, lights, etc. into a single harness rather than individual wires. If it is preferable to wire direct, the WOW101 is likely the better option.
  • Am I going to replace any bulbs with LED's?
    • TCS motherboards have on-board resistors for use with LED's. WOW101 decoders do NOT have integrated resistors. If using anything other than 12V bulbs, external circuitry/resistors MUST be added.

Your answers to these questions will determine if a hard-wire job or a kit installation are right for you and for your locomotive.

Question: I have (x) locomotive. What decoder do I need?

First answer these questions:

  • What scale?
  • Do you want sound?
  • Will this engine be run on DC or DCC?
  • Have you searched our Installation Resources for your model?
    • If you answered "Yes" to sound, search only the WOWSound Installations.
    • If you answered "No" to sound, select your scale.

Use the search box at the top of the page to narrow the list down by manufacturer or locomotive type. We recommend browsing by manufacturer to see all of your options.

I wasn't able to find my specific model. Now what?

If you cannot find your specific model in our list of installations, you can submit pictures of your model with the shell removed to our team via Facebook or via Email

Four Digit Addressing

CV1 cannot be modified on the main via OPS mode programming, and cannot have a value greater than 127. If you would like to program your locomotive with an address such as a road number which is greater than 127, you must use a 4-digit "Long" address. In this case, the word "digit" refers to the four block binary-coded representation for the address, and does not mean there needs to be four numbers to your address. For example, a 4-digit "Long" address may be any address between "0000" and "9999".

To enter a "Long" address manually, you first need to convert the road number or other desired address number to "binary-coded decimal" using a calculator tool.
Use the values calculated for CV17 and 18, and enter them into CV17 and 18.
After those values have been entered, you need to change the addressing type for that decoder to LONG addressing. If you have not changed the default configurations, program CV29 with a value of 34. If you have, or aren't sure, first READ CV29, and then ADD 32. Program the SUM into CV29. You can also use our CV29 calculator to determine the necessary value based on your desired configurations:

Some command stations have a method of automatically entering a 4-digit "Long" address which will automatically calculate and program these values, including CV29. You can refer to your command station user manual or manufacturer for more information.

Function Remapping

Function mapping of lighting outputs can be done via the programming of Configuration Variables or via Audio Assist on WOWSound decoders. The chart found in the Comprehensive Programming Guide shows the CV's and values that correspond to the function outputs and function buttons. In the DCC standard for packet transmission (that is, the communication over the rails) function buttons for lighting are separated out into two packets, with functions 0-6 being in the first packet, and Functions 7-12 being in the second packet. As such, if a function is going to be assigned to respond to a command in one of these packets, it needs to be configured in that CV. As you see on the chart, Functions 1 - 6 have TWO CV's. The CV on the LEFT of the chart can assign a button from 0 - 6 to that function. A value of ZERO in any of these CV's will disable the function from responding to any button from 0 - 6. Along the RIGHT of the chart are the secondary CV's which correspond to buttons 7-12. By default, these CV's are 0. By programming a value to these CV's, a button or buttons can be assigned to activate the function from 7-12. Note that it is possible to have multiple buttons control the same function using this method if desired. It is suggested that only one CV for each function be programmed with a non-0 value to prevent de-synchronization or confusion.

Along the TOP of the chart are two sections of values from 1 to 128. The numbers from 0 to 12 listed above the values state what value would correspond to that button number. By programming the value listed below a button number, that button will be assigned the function whose CV was just programmed.

It is important to know the difference between a FUNCTION and a BUTTON.

  • A FUNCTION corresponds to a numbered function pad or a colored wire from the decoder. For details on which color of wire corresponds to a numbered function output, refer to the NMRA Wires and Connector Standards
  • A BUTTON is located on your throttle or control device and does not necessarily directly correspond to any output from the decoder, as this can be configured.

[Example: You are attempting to move a function to the higher function group. F2 -> Button 8. To do this, once again look at the chart. Function 2 has two CV's - CV36 and CV38. Button 8 is part of the higher functions, which would make use of CV38. Therefore, by selecting the value that corresponds to Button 8 (a value of 8), and programming that value into CV 38, Function 2 will now respond to Button 8. To finish the transfer, we need to clear the button from responding to Button 2. To do this, program CV 36 with 0. Now you are finished!]

Heat and Decoders: How Hot is Too Hot?

Question: How hot should my sound decoder get?

WOWSound and other TCS decoders should never get hotter than can be touched comfortably. You should be able to grab a hold of the decoder and not burn yourself; however, our decoders can get up to about 100 degrees based on the conditions presented to them without much of an issue - that would be a normal operating condition.

Things to look for would be the origin of the source of the heat. If your decoder has shrink wrap, look for places where it may be stretched - indicating heat is prevalent in that area. Also, if the amplifier is being "taxed" or overdrawn, it will get very hot. Conditions that would cause this would be:

  • Using a speaker which is rated at less than 8 Ohms and less than 2 Watts
  • Pumping 100% volume into a speaker which is not rated for 2 Watts or greater
  • Having a speaker with a loose cone or similar mechanical failure

These are the leading causes of excessive heat in regards to the audio amplifier. As a test, you can disconnect the speaker, or mute the decoder for an extended period of time to see if it cools off.

WOWSound audio amplifiers can supply upwards of 2.2 Watts of power at 100% volume into an 8 ohm speaker. If your speaker is not rated for 2 or more Watts, but is being supplied with a 100% volume output, the sound will distort and possibly pop and click.

If you are hearing distortion in the sound quality and/or have a hot decoder, it is recommended to reduce your master volume by at least 10%. If you are still hearing distortion or clicking when playing loud sounds like a longhorn/longwhistle, reduce by an additional 5% until it goes away. Each press of button 1 in the master volume menu of Audio Assist reduces the master volume by 5%. Don't forget to save your changes with button 8!

The resistance across the speaker should read between 7.2 and 8.8 Ohms. Readings outside of this range would indicate a failed speaker.

I tried these steps above and the decoder did not cool off.

If the heat source is not related to the audio amplifier, meaning it is still hot while the sound is muted for a long time or the suggestions above have made no difference, you may consider the following:

If the decoder is only hot after running for LONG periods of time, this is a reasonable condition and should not damage the decoder. Failures related to motor control tend to happen quickly, so if you can observe reliable long-term operation, there should be no reason for concern. Give your engine a break every once in a while or at slower speeds if you are concerned.

If you are not observing excessive heat during stationary conditions, it is likely that the heat is being created by the motor drives which is normal. If the heat is excessive, you may consider testing your motor current draw. Next check the current rating of your decoder to make sure you are not exceeding its capabilities! Current ratings of decoders can be found on their product page under the tab labeled "Specs". Note that these current ratings are for the entire power supply - motor, lights, and sound if applicable.

Keep Alive® Compatibility

NOTE: ALL TCS decoders are compatible with Keep Alive®! Yes that includes N and Z scale and Fleet Lighter decoders! All TCS decoders are also defaulted to support Keep Alive® without any programming. Just plug and play!

Keep Alive® supported code for TCS decoders was implemented fully by November 2012. If the date code in your decoder is before this date, Keep Alive® may never enable. Other decoder manufacturers have since followed with their own support for the device. You may need to consult your decoder manufacturer regarding their own support for Keep Alive® on specific devices. CV's 250, 251, and 252 read as the month, day, and year of manufacturing.

If you would like to attach a Keep Alive® unit to a non-TCS decoder, you need to connect the wires across the output of the bridge rectifier on the decoder. You will need to consult your decoder manufacturer for a schematic or wiring diagram if you are not able to locate these two points on your decoder:

  • +12Volt DC Common (Blue wire on KA devices)
  • Decoder Ground (Black & White wire on KA devices)

If you are able to find these two points on the decoder, solder the two Keep Alive® wires and you are finished. Remember Keep Alive® operates on DC, so attaching the unit to track power will do nothing if not destroy the unit. Also, note that the black/white wire is the Ground on Keep Alive® units.

All Keep Alive® devices operate in the same way and are equally compatible with any decoder. KA1 and KA2 devices have equal capacities to each other, and are approximately 1/3 the capacity of the KA3 and KA4 devices while at the same time being roughly half the size of their counterparts. Physical dimensions are the only considerable differences between Keep Alive® devices. These dimensions must be taken into account prior to installation, as choosing the wrong device may interfere with the installation.

For more information on Keep Alive®, click Here.

For more information on our new KA1 and KA2 devices, click Here.

Light Mode vs. Sound Mode

WOWSound decoders have two operational modes: Light Mode and Sound Mode. When first powering up a WOWSound decoder, it will default to Sound Mode. In order to access your light functions beyond F0, you must enter Light Mode. (Unless otherwise user-configured)
To toggle operational modes, you must press Button 8 on your controller twice in rapid succession. You will hear an announcement from Audio Assist® announcing the active mode. In order to change back, just press button 8 twice again. If you switch too fast, however, the decoder may register 4 presses and enter the Audio Assist® program.

In sound mode, you can use buttons 0-27 to control sound functions. In Light Mode, you can use buttons 0-12 to control lighting functions. Both modes can be remapped using Audio Assist or CV programming, but you should refer to your decoder literature for the default mappings. By default, Light Mode buttons will correspond directly to their numbered function output unless otherwise programmed.

Check out our video on Operational Modes:

Lights - The Rules of Wiring Incandescent Bulbs

The precise wiring of your locomotive's lights is ultimately at the discretion of the end user. However, a few rules do apply.
When using incandescent bulbs, observe the voltage rating - 12V bulbs must be connected to the 12V supply. 1.5V bulbs may be connected to 12V but only through a resistor with appropriate ratings; alternatively, a TCS VR1.5 may be used to provide a regulated 1.5V supply for all of your lights. Some TCS motherboards have dedicated 1.5V power supplies on-board for these bulbs, but not all motherboards. Your literature will distinguish this. If you are installing an Athearn locomotive which has not had the factory bulbs replaced, you are to use the 1.5V power supply as the positive voltage source for your lights. Additionally, some motherboards have dedicated contacts for "bulbs."

The NMRA standards and specifications designate the use of White and Yellow wires for headlights. To White is assigned "Function 0 Forward" for use with a forward headlight, and to Yellow "Function 0 Reverse" is assigned for use with a reverse headlight. If your decoder does not use wires (motherboards for example), the literature for your product will include a wiring diagram designating what connection(s) correspond(s) to a function. For a full list of NMRA wire color codes, click Here.

All light functions can be remapped or reprogrammed for your desired operation. For more in-depth details on function remapping and output assignment, I would highly recommend browsing through our Comprehensive Programming Guide. This guide covers all the essential information pertaining to basic decoder configuration, as well as how to assign function outputs and effects. See our help section on function remapping for more.

TCS connectors and harnesses are available with colored wires to connect lighting and other functions. You can view our page listing all of our wiring and connector standards by clicking HERE.

Lights - The Rules of Wiring LEDs

When using Light Emitting Diodes (LED's), you must always include a resistor in series to limit current UNLESS your TCS product has on-board LED support. Refer to your decoder literature, wiring diagram, or the silk screen on the board itself for LED connection points (if applicable).

If using Light Emitting Diodes, polarity must be observed, as a reversed connection will not work. Diodes have two connections known as the Anode, which is a (+) connection, and Cathode, a (-) connection. When working with decoders, the Anode(+) connection is to be connected to a common voltage source, and the Cathode(-) connected to an individual function output. These connections will be noted in your decoder literature or on the silk screen of the product itself. The NMRA determined that DCC decoders are to be designed as "Common Anode" devices, meaning there is to be ONE, COMMON, POSITIVE voltage source, and individual returns to ground(-).

BLUE is the color designated by the NMRA to be used for the common Positive Voltage Source. On decoders, this can be designated as a Blue wire, "BL" or "+", or similar. As many lighting functions as needed are to be wired to this one point. Some decoders have multiple connection points for ease of installation.
Each function on a decoder is given an associated color and function number to serve as a return to ground. When using LED's, these connections must be made to the cathode (-).

The NMRA standards and specifications designate the use of White and Yellow wires for headlights. To White is assigned "Function 0 Forward" for use with a forward headlight, and to Yellow "Function 0 Reverse" is assigned for use with a reverse headlight. If your decoder does not use wires (motherboards for example), the literature for your product will include a wiring diagram designating what connection(s) correspond(s) to a function. For a full list of NMRA wire color codes, click Here.

All light functions can be remapped or reprogrammed for your desired operation. For more in-depth details on function remapping and output assignment, I would highly recommend browsing through our Comprehensive Programming Guide. This guide covers all the essential information pertaining to basic decoder configuration, as well as how to assign function outputs and effects. See our help section on function remapping for more.

TCS connectors and harnesses are available with colored wires to connect lighting and other functions. You can view our page listing all of our wiring and connector standards by clicking HERE.

Mainline Programming

Programming an address "on the main" is complicated for a few reasons. The first complication is that CV number 1 may never be programmed on a mainline in OPS mode - This is a DCC standard set by the NMRA. Therefore, if you plan to program a short address, you must use a programming track. If you want to program a long address into a decoder using your mainline, see our help section on Four digit Addressing. Mainline programming is 100% reliant on the address of the locomotive to perform programming. Here are the problems with that:

  • Having multiple decoder on the same address
  • Having multiple decoders in the same engine
  • Not knowing what the address is/Accidentally scrambled the address
  • Selecting the wrong address and instead programming a different decoder by mistake

When setting addresses, TCS recommends only using a programming track and never re-configuring the address on the main.

The only benefit of mainline programming is the speed at which programming operations can be performed. It is not necessary to wait for confirmation or read-back on each operation. Unfortunately, the trade-off is that without the technology such as RailCom/RailCom+ it is not possible to perform mainline program read operations. Mainline programming is only recommended for on-the-fly changes that need to be performed in real time or if you are experienced with CV programming.

Marker Lights

A common request we receive is marker lights that are active in the opposite direction of travel. The directionality of lighting effects is based on the value entered in for that lighting effect generator. CV's 49-56 can be programmed with values to determine the lighting effect as well as the direction of that lighting effect. For example, a constant bright light in the forward direction equates to a value of 0; in the reverse direction, this value is 16, and for both directions (the default value for CV's 51-56) 32.

For the above case, light functions tied to the lights opposite the direction of travel need to be programmed with the value which corresponds to the direction of travel. For example, the lights on the rear of the engine would be programmed to be ON in forward, and the lights on the front of the engine would be programmed to be ON in reverse.

Please consult page 7 of the Comprehensive Programming Guide for the full chart of effects and the corresponding directional values.

Manual Calibration (WOWDiesel)

It is possible to "dial in" the BEMF calibration via CV programming. If the automatic calibration didn't quite get it right, you can manually modify the BEMF settings. To do this, perform the following operations:

It is necessary to first know the existing calibration values prior to adjusting them so that you are not programming randomly or blindly.

CV201 = 104
CV202 = 17
CV203 = 0
CV204 = 0
READ CV204: This is your current LOW BEMF setting "idle setting" in which you will be notch 1. Decreasing this value will mean that notches 2-8 will happen sooner with lower loads. Increasing this value will require more "load" to increase the notch.

CV201 = 104
CV202 = 18
CV203 = 0
CV204 = 0
READ CV204: This is your current HIGH BEMF setting "notch 8 setting." Decreasing this value will decrease the dynamic range, resulting in faster notch transitions.

CV201 = 4
CV203 = [17 OR 18] (High/Low BEMF setpoint)
CV203 = 0
CV204 = [Your Desired Value]

It is advised to work in steps of +/- 5. If you find that you have gone one step too far, go backward by a value of 2.

Additional information on how to manually calibrate can also be found in our WOWDiesel Programming Guide.

Smoke Unit Enable (WOW501)

To enable the smoke unit in the WOW501 program CV58 to a value of 9.

F5 turns on the coil and F6 turns on the fan full blast. These functions must be tied to those specific outputs. F6 is automatic, and does not need to be turned on with your throttle, otherwise the output will turn on full blast until it is turned back "off" to automatic. Those two outputs can also be used as on/off only. Depending on the coil unit you are using, it is recommended to change F5 to a "constant dim" effect which limits the power to the coil. This will extend the life of your coil, and prevent overheating in most cases. The dim generator you select can then be configured to a power level using the corresponding CV. This CV should be set to a level high enough to start producing smoke, but not much more.

[Example: CV55 = 44 CV64 = 1-30 {Your Desired Heat Level - depends on coil itself}]

Speakers - Wiring Multiple

When wiring a multi-speaker arrangement, the resistance of the individual speakers must be observed. TCS amplifiers are rated for 8 Ohms of output impedance at 2 Watts. If you have two 4 Ohm speakers, you must wire them in series. 8 Ohm speakers should also be wired in series unless the total wattage exceeds 2.5 Watts. Alternatively, you can also wire in parallel with a resistor in series, in order to match or exceed the 8 Ohms. Exceeding the load (resistance) rating on the amplifier will not cause stress, but may reduce the maximum volume output. Exceeding the power (wattage) rating of the amplifier will not cause damage to the amplifier.

Warranty - Decoder Upgrades

WOWSound decoder upgrades are available via our website, which you can go to by following the link below. We charge $25 per decoder plus return shipping, and offer a discount for the more you send in at once.

We do not offer official shopping cart items for non-sound upgrades, but do offer upgrades on non-sound decoders when submitted. The fee for any non-sound upgrade is $16, and can easily be added to your invoice by our staff prior to return shipment.

WOWSound decoder upgrades can be found on our TCS shopping site.

The instructions for submitting a WOWSound decoder upgrade will be in the confirmation email you receive once your order is placed, but to narrow it down, here's what you need to do:

  1. Print the confirmation email with RMA number
  2. Package the returning item(s) in a small box, and also include the RMA form
  3. Send that package to the P.O. Box 341 Blooming Glen, PA 18911 listed on the form as "ATTN Upgrade"

You'll receive updates via email about the status of your return, including when it is received, when it is processed and upgraded, and when it ships. You will also receive a USPS tracking number when we ship.

Warranty Submission Process
For detailed information on submitting a TCS product under warranty, including details on what is covered, please visit our Warranty section.

Multimeter Troubleshooting

NOTE: This section requires the use of a digital or analogue multimeter to perform electrical checks.
NOTE: Continuity checks that include the rails must be performed with one lead connected or touched to the rail.
NOTE: ALL resistance measurements including continuity MUST be performed with the power OFF.

Check resistance/continuity for the following:

  • Left Rail to Right Rail
  • Orange to Grey (motor connected)*
  • Orange to Grey (motor disconnected)**
  • Left Rail to Orange
  • Left Rail to Grey
  • Right Rail to Orange
  • Right Rail to Grey
  • Speaker contacts (speaker disconnected)***

NOTE: NONE of the above tests should read 0 or near-zero.
*Orange to Grey with a motor connected should read between 50 and 200 Ohms for a typical HO-scale motor. A reading below 50 or near-zero indicates a shorted motor or wiring.
**Orange to Grey with the motor disconnected should be a non-zero value of approximately 20K Ohms.
***Only applies to SOUND DECODERS - An 8 Ohm speaker itself should read Between 7.2 and 8.8 Ohms. If less than or greater than these numbers, the speaker has failed or is failing and should be replaced.

Check resistance/continuity for the following:

  • Left Rail to (Black) Power Pickup on decoder
  • Right Rail to (Red) Power Pickup on decoder

NOTE: These readings should be near-zero and not fluctuate.
Check DC voltage for the following:

  • Blue wire to ground
  • Orange to Grey (this test must be done with the motor disconnected) Gradually increase the speed step. You should see the DC voltage increase from 0 to ~12V. Reversing direction will also reverse the polarity of this reading.

Check AC voltage for the following:

  • Left Rail to Right Rail

NOTE: Voltage measurements are to be performed with power applied to the engine.


If you have additional questions, please reach out to our Technical Support
team through email or by phone during our open hours. Thanks!
 TCS Technical Support