Support - Motor Control

This support article will help you troubleshoot and diagnose common motor-related issues.

Motor Runs Backwards of Indicator on Controller and/or Lights

For newcomers to DCC installation, a common mistake/issue is having the locomotive drive backwards of the expected direction after the installation. An additional observation you may have is that your directional headlights are opposite of the direction of travel. There are multiple solutions to this problem - The most important step to solving this issue is observing the direction of the throttle/controller with respect to the directionality of the locomotive's motor and its light functions. Assuming you have not done any CV programming, the headlight functions will always follow the direction in the DCC packet being sent to the decoder. This means that when your throttle shows "Forward" the 'forward' headlight will be on if F0 is on; likewise for reverse.

If the motor control alone is reversed of the selected direction of travel, meaning the headlights are correct with respect to your throttle, the best and simplest solution is to swap the orange and grey wires to the motor. This will possibly require disassembly of the model and re -soldering the motor wires to the correct pads/wires/contacts.

If the lights alone are reversed of the selected direction of travel, you should fist ensure that CV29 is not improperly configured. If CV29 is an even number (meaning the directionality of the decoder has not been reversed intentionally) you may have mistakenly wired the forward and reverse lights to the wrong ends of the engine. If you have done any CV programming, you may have mistakenly entered incorrect values for the lighting effect CV's (49 and 50).

If BOTH the motor and lights are reversed of the direction of travel indicated on your throttle, the easiest solution is to reconfigure CV29 to reverse the directional conditioning of the decoder. Refer to the CV29 page for information and instructions on how to configure the direction.

Version 5 Addendum

In WOWSound Version 5 , we have changed the behaviour of CV29's direction bit. For more information on CV29 in Version 5, click HERE. From our experience with CV29 the main reason to use Bit 0, the direction bit, was to solve the issue described above (where the direction of the motor did not match the direction of the lights due to a wiring mistake); however, the previous behaviour of CV29 which reversed ALL directional settings in the decoder, including the lights, would not solve this issue.

As such, in Version 5 decoders, the direction bit of CV29 reverses the directional control of ONLY the motor. This means that you would no longer need to disassemble your model to rewire the motor and solve the problem.

No Motor Control

Loss of Forward OR Reverse Motor Control

The most common reason why a locomotive would not have motor control in one direction and not the other tends to be intrinsic to the motor itself, particularly the brushes. This issue often presents itself on steam locomotive models, as they tend to run primarily or exclusively in one direction and rarely, or never, the other. What tends to happen is the brushes will have a wear pattern which is suited for running in that one direction, and not the other; therefore, when reversing direction the brushes may misalign and not make proper contact. In this case, a gentle tap or bump in the right direction may get it moving by re-situating the brushes.

Another reason, similar to the previous, can happen as a result of carelessness when wiring the motor. If the wires that connect your decoder to the motor were soldered by yourself directly to the terminals on the motor, this can often load to overheating of the contact, wires, spring, etc. or even the brushes and commutator in extreme cases. The result of this can vary from the buildup of oxides, leakage of flux into the motor itself, or melting of thin internal wiring and springs, any or all of which can create an [inconsistent] open circuit.

Loss of Motor Control in Both Directions

Complete loss of motor control is a common occurrence which tends to result from two main possibilities.

1. Bad/Incorrect wiring
2. Consisting

Issue number 1 will present itself typically during or shortly following a new installation or rewiring of a locomotive. The solution for this is simple - inspect and repair your wiring, ensuring proper solder joints and otherwise secure connections.

Issue number 2 tends to present itself after longer periods of time. You may say to yourself, "I've had this decoder and locomotive for years and it always ran great at the club! But now I've gotten it down of the shelf and it's not running. What gives!?" 9 times out of 10, possibly even 99 times out of 100, The reason for this behaviour is a CV 19 Consist. There are a few ways to identify this as your issue. For example:

• Light functions are behaving as normal (except perhaps when the direction is reversed)
• The engine sound does not rev up, or the chuff does not begin playing when the speed is not 0
  • Note: On A TCS decoder, If the motor has an open circuit and BEMF is enabled, the Prime Mover will jump to Notch 8, or the chuff will play at maximum volume. This is because BEMF is considered to be art the maximum possible amount at a "full stall" (no motion).
• Using the brake release doesn't do anything
  • Note: On a TCS decoder, the brakes will automatically release when you increase the speed, preventing a common issue you will have with other decoders where the engine refuses to move until you 'remember' to release the brakes.

If you observe any or all of the above symptoms, your locomotive is in a CV 19 Consist. Programming CV 19 with a value of 0 will solve this issue.

In our experience, this issue tends to happen most often to users who frequent train clubs. The circumstances for how the locomotive became consisted will vary, from "whoops" moments to intentional changes which were forgotten with time; regardless, you have a few options to protect yourself from this conundrum:

Option 1: Decoder Lock <<Click the link to learn more

Option 2: (WOWSound Only) User Presets <<Click the link to learn more

Option 3: CS-105 Automated Address Programmer <<Click the link to learn more

In a similar vein to both of the previously described issues and solutions, one other possibility which has been observed on rare occasions has to do with the actual wire used to connect the motor - In combination with connecting the wire too close to the brush cap, if said wire is very stiff, it can apply leverage on the brush cap. We have only seen this one one recorded occasion, but the issue was very difficult to reliably reproduce or troubleshoot - vibrations of the motor both from the rotation itself as well as any external movement could cause the brush cap to lift up and open the circuit, stalling the motor.

Other Issues

If you find that the information in this article was not as helpful as you hoped, and you didn't find the solution you were looking for, you may consider looking through the other motor-related settings, CV's, and help articles. To browse the full list of motor-related subject mater on this Wiki, click the Category listing below for "Motor."