Pcm,Vrm, and openmesh radio will not work on or come on

Just a few hours ago everything was working fine come back in and none of them will turn on. Any help with troubleshooting?

Check the one common 20a fuse (yellow) on the PDP that leads to all of those.


As Mark said, pull the yellow 20a fuse out of your Power Distribution Panel and hold it up to the light. If the horseshoe shaped bit of metal inside is disconnected it means you have blown the fuse and need to get a replacement.

We’ve seen issues with a compressor attached to the PCM kill that fuse multiple times.

If the fuse pops again, trace down the root cause.

Two quick notes a compressor shouldn’t cause that, if it does replace it. Secondly you can attach your PCM with the compressor to a wago slot with a 20 amp breaker instead of the fused slot, to mitigated any future issues. (R52)

The start current on many legal compressors can approach 20 amps under some conditions. The robot rules do allow you to connect the PCM to a standard PDP output through a 20 amp resettable circuit breaker. Holding the yellow (or red) fuse up to the light may not show a failure. Use your multimeter set to “cont” or ohms to insure that the fuse is actually very low resistance.

Also first check that the two small fuses on the PDP are actually plugged in all the way. The sockets are tight, if it’s a new PDP, then it’s hard to get them fully seated, and the symptoms are exactly what you describe.

random internet pic (thanks team 358!) of a seated, and an unseated fuse


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