Hi all, been on here a while and while searching almost always answers my question, I'm truly stumped on a PASM issue.

I recently installed H&R lowering springs on my 2005 Carrera and getting a persistent "PASM Indicator Faulty" message after startup. Durametric is unable to communicate with the control unit and the fuse for the control unit keeps getting blown immediately on startup (Row C F9 15 amps). I believe this fuse is dedicated for the control unit itself and isn't combined with any other systems. I have thoroughly inspected all the PASM leads from the shocks for damage and made sure all the connections are seated properly. I also pulled out the PASM control unit and extracted the circuit board from the plastic housing. I couldn't see any tell-tale signs that the board is fried, it all looks in order. Based on this does anyone think the PASM control unit could still be fried? I'm curious how simply unplugging the PASM leads and reconnecting them could fry the control unit. Also are there any other causes for a short on this system other than a frayed wire or unseated connection that I should be inspecting? Kind of hard to diagnose this issue with the control unit not work but hoping to avoid pulling the trigger on an expensive new control unit.

Thoughts?

 

You may have nicked the wiring into the shocks. If you haven’t done it already, I would unplug all four corners and the see if the fuse still blows. If not, reconnect one by one.
Good luck.
Cheers,

 

If you need a known good PASM control unit, I have the one from my 05 S sitting in the parts cabinet from when I installed TPC's DSC controller that I'd sell as I'll never be selling this car or going back to the stock PASM unit. If further testing reveals it's probably a bad controller itself, let me know and we can work out a price.

 

Have you checked the leads going to the shocks for shorts? A mm with continuity function would tell you that. You could also measure from the controller side. If the wire is pinched somewhere you can't see that would tell you which one. I would also check to see if one of the shocks is shorted internally. Spring swap may have damaged one of them.

 

Good thinking, I will try this and report back.

I will definitely reach our when I confirm I need one! Thanks!

Could you elaborate on how to check that side of things for shorts?

 

A multimeter can check for shorts. 0 ohms is a short. Some of them have a continuity function which will beep if there is a short. It also puts more voltage on the checked circuit to ensure an actual short. Check from the terminal on the shock to the body ground. Check all 4 shocks. They should be the same give or take a few ohms. If any are zero when the others are not, that could be your culprit.

 

Awesome, thanks for the detail! experienced in a lot of mechanical diy, not much in electrical!

 

Make a diagnosis on this one?