Digitrax Hints: Throttle Troubleshooting

Summary: Hint and trouble shooting issues with issues with Digitrax Throttles.

As these are electronic devices, please Read and Follow the ESD guidelines before handling them.

Throttle Problems

These devices are handled a lot, and there is always the possibility that they will be dropped or receive an impact. Handle them with care, as rough handling can cause damage.

Avoid pinching or crushing the cable, this can damage the wires inside. Avoid repeated flexing of the cable in the same place, as the wires will eventually break.

Internal Issues

The easiest troubleshooting step is to give the back of the throttle a good slap with your hand. If the problem goes away, there is likely to be an intermittent connection on the throttle's circuit board.

To fix it:

• Carefully open the throttle
• Press down on any socketed ICs on the board to reseat them.
  • Don't use excessive force, as it is possible to flex and damage a PCB.
• Testing the throttle can be done at this point by connecting it to the LocoNet
• If everything works as it should, close the case.

If during this process you observe components which don't look right, such as a leaking or damaged capacitor, seek advice from an electronics tech or Digitrax. There may be other problems in play.

Cable Issues

A common cause of the IDLE warning is a bad cable connection. The repeated flexing of the tethering cable at the RJ connection can break a wire. This can also occur at the point where the cable enters the throttle's case.

• Wiggle the cable at the plug and watch the display to see if anything changes
• Wiggle the cable at the throttle end, and watch for changes

If the IDLE issue goes away, the problem is a bad wire.

The solution is simple:

• Cut the RJ12 connector off
• Trim back the cable a little
• Install a new RJ12 connector
  • Ensure the wires are in the proper position before crimping
  • Use the proper RJ12 and a good crimper
    • If the plug was previously replaced, the type of RJ connector may have been the issue. Use one designed for the type of wire used.

If the issue appeared at the throttle end of the cable:

• Open the throttle
• Cut the cable outside the throttle case
• Unsolder the connections inside the throttle
• Again, pay attention to the colours of the wires and where they go
• Cut a few inches off the end of the cable and strip
  • This eliminates the chance of a broken wire.
    • If the cable was cut off several inches from the throttle case, this step is not required
• Strip the individual wires and solder in the appropriate position
• After completing this step, ensure any socketed ICs are seated correctly. Expansion and contraction during use can push them up, making a bad connection. Good practice, as they may cause an issue later.
• Close up the throttle

Further Reading

• LocoNet
• Digitrax Hints