Pneumatic Control Module Power Issue

[Mr V]

Originally Posted by billbo911

Right, dedicated power for the PCM, forgot about that.

Now I'm even more confused. How could they have measured 12 volts on the PCM board, yet had an open fuse feeding it?
There must be some new magic in the control system for 2015.

Well it is unlikely for the standard automotive fuse to fail in this manner but if a tiny portion of it is still connected it will flow enough current for a volt meter with a 10megaohm input impeadance to show "12v". However it won't flow enough current to power up the board. This can also happen with really bad connections. For this reason a volt meter is a poor tool to check for power on a load level circuit. You need something that will put some load on the circuit like a test light.

[KettleFallsTeam]

Well, we replaced the fuse and we are getting the same results. However, after listening to the discussion here, we must have burned out the fuse while playing with things after it was already not working. We have checked some of the parts on the board. The little fuse on the PCM is still good. Voltage is going in to the pins on the board. Unfortunately, the overnight shipping to Washington state is $70 but, I'm thinking we will just do the advantage shipping as saving one day doesn't justify the $70. If only they could fulfill the order faster than three days.

Thanks for the all the help, we have an electrical engineer poking around the board right now as I type so, I will keep people posted on what may have happened.

Cheers!
Canine Crusaders #4980

[nedwards28]

Well, I said I would update, so here I am. I think while younger teammates were working in the control system wires were pulled or inserted when it was on. Taking a look at the PCM, we couldn't see any processing going on or any indication that it was working beyond power in.

We contacted Cross the Road and they replaced the module for us. They were exceptionally helpful and easy to work with with.

Thanks everyone! Good luck in the last few hours!