Electrical gremlin

[Arodrigues29]

2001 24v 5spd 4x

My truck struggled to start slightly and clunked at 2K rpms in second pretty loudly and before I could pull off it did it again 1800 rpms in 3rd this time my headunit, trailer brake controller went off and back on and my lights started doing the rave party flash. Shut the truck off, checked my battery terminals everything looked cherry started it back up no issues. About 5 mins from home my gauge lights started flickering and my volt gauge spiked to 18. I had a battery terminal that was suspect and new batteries sitting around so I tossed them in, wire brushed the connections. 2 weeks of perfect driving and today it happened again, skip in second, hardish start headunit flash. This time when I turned the truck off it wouls not restart, no hazards, no power whatsoever. Took off positive battery cable on drivers side battery and reapplied it, truck fired right up w/ engine light for high voltage. Truck got me home, lights a little flickery. I cleaned all my grounds within the last 6 months, alternator tests good. Direction?

[notlimah]

What was the ac voltage on the alternator?

 

Bad ground any where?

 

ECM fried?

[IBMobile]

How do the wires and connections in the power distribution center (PDC) look?

Start with the main cable from the left side battery to it.

[Arodrigues29]

13 hours ago, IBMobile said:

How do the wires and connections in the power distribution center (PDC) look?

Start with the main cable from the left side battery to it.

PDC looks good. I just went to start the truck and it had no power again. I unplugged my Quad ADR and it fired up no issue. 

Edited July 9, 2017 by Arodrigues29

[Dieselfuture]

Mabe reflash your qwad, are you using v2

[kzimmer]

Quad can't cause your radio to lose power... But I wouldn't plug it back in until your issues are resolved. You said you had a code for high voltage? Check DC voltage while the truck is running. If it's high, don't run it, the previous owner of my truck ran it with a bum voltage regulator (possibly internal to PCM, someone else can verify this) and it fried.... Everything. Window motor, power seat motors (all of them!), bulbs... Not sure about VP44/PCM/ECM I just replaced what was still broken when I bought it.

[trreed]

I did have a funky flash on my quad once that randomly caused rpm and canbus values to get stuck in the ecm, causing the truck to run away, catch itself, and die.  A fresh flash and the problem has yet to return months later.  So it might be a possibility.

I would check the voltage regulator, AC and DC voltage, and maybe reflash the quad to start.

Edited July 11, 2017 by trreed

[Me78569]

high voltage is normally a bad ground in my experience.  

 

Flash the Quad for good measure.

[kzimmer]

That may be... But I'm yet to see a piggyback programmer cause truck-wide electrical issues, shut a radio/trailer brake controller off, etc. But who knows, I'm excited to see where this goes, haha. Good luck Arod.

[Spike48]

Check your grounds.  I was having an issue with torque converter unlocking randomly.  I could trigger it by quickly turning the heater fan on high as well.

 

I pulled and cleaned the ground on the frame at the front of the truck on the driver's side as well as unplugging and inspecting the inline ground connectors at the batteries.  Problem solved.

[Arodrigues29]

Took everything I could apart as far as grounds go again and reflashed the Quad. No luck. I jiggled the positive cable to my PDC by happenstance and sure enough it was loose. Seems like the nut backed itself off the terminal a bit and it arked in there. Some emory cloth and wire brushing, tightened it back down and 2 days of everything seemingly being ob kb. My passenger heated seat isn't even turning on by itself! Thanks for the help as always guys

[trreed]

Good to hear!

[notlimah]

saweet!