PCM not providing 24 volts to solenoids

We’re using these brand solenoids from AutomationDirect with a PCM that has been sitting around a while. We switched the jumper on the PCM to 24v, but we only get 12v out of the solenoid outputs (measured with a multimeter). The LED on the currently-outputting PCM channel lights up when triggered via software and the LED on the solenoid lights up as well. All other functions (compressor and pressure switch) appear to work normally. All solenoids work via the manual valve (red indent).
Is there anything else to check? Should we cut our losses and just get a new PCM?

Edits in bold

If you look at the PCM User guide under §1.2 it says that the compressor always outputs 12V. The jumper only boosts the solenoid outputs.

If you look at R86, you’ll see only 12V compressors are legal for use in FRC. If you had a 24V compressor you were planning on using for your robot, it’s not legal even if you could power it from the PCM.

Edit: is the problem that the compressor output is only 12V or that the solenoid outputs are only 12V (or not working). It’s not really clear.

Whoops! I meant 24v on the solenoids outputs. I’ll update the original post.

That makes more sense. Can you post a picture of your PCM and attached wires?

I can post a picture on Monday when I get back to the shop. Right now, we have 3 of the solenoids I linked above in solenoid ports 0, 1 and 2. We also have the pressure switch and compressor plugged in to their respective ports. The status light behaves as expected (green blinking, faster when enabled). All wires have ferrules attached.

Edit: The more important part, we have the jumper in the 24v position.

1 Like

Here are a couple pictures. I verified that the PCM status light blinks green when the robot has power.


I don’t see anything here that would cause the problem you described. Unless someone else on here does, you should probably contact CTRE support. They’re usually very helpful with these kinds of problems; they know their products better than anyone else and can repair/replace anything that’s been damaged.

Side note related to the picture. I would replace that bottom CAN bus ferrule in the PCM. There is a lot of copper showing and with a CAN bus system I wouldn’t risk it.

1 Like

Okay. We’ll contact CTRE. Thanks for your help!
@ns3517 I’ll replace that ferrule too.

@ozrien any ideas? Should I send a message to CTRE support?

Have you tried checking the inside of the jumper opening for aluminum that could be shorting the pins?

Be sure that the jumper you are using is shorting the pins for the 24 volt selection. The jumper may be open.

@21brownz @Al_Skierkiewicz I’ll check both of those things next time I’m in the shop. I’ll also try to take a couple of pictures when I open up the case.


Yes, contact our support at support@ctr-electronics.com
This goes to me and several of my staff whose job is to help you.

Also mentioned here…
And here…

CD is not an official support forum, I’d say its more of a community sanity check for common gotchas.


Looking at your photos the obvious root-cause would be the jumper is not actually in-circuit. It appears to be wrapped in heat-shrink or electrical-tape, which, at a minimum, makes it suspicious.

A self-test wouldn’t hurt either, since it reports the measured solenoid voltage and previous sticky faults.

1 Like

Thanks! I’ll send a message to CTRE support and run a self-test when I have access to the robot.

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.