Got a jump start... now my gauges die and my radio shuts off and...

[bobc455]

This morning I had to call AAA for a jump start. Without giving too many details, the jump start was very poorly done and I think it fried a computer or ???

2004 GP GT, basically all stock.

Here are my symptoms:
- Everything works fine for about the first minute after the engine is running
- Then the speedometer drops to 0, the tach drops to 0, the temp gauge goes to full cold (even if engine is hot), the gas gauge drops to E, and I get the "Low Gas" alert from the DIC, all simultaneously
- Also, my odometer will only read "error" instead of displaying the mileage or trip odometers
- If I shut off and restart, it all works well for another minute but then craps out again
- Radio comes on very sporadically (but never when the gauges have all dropped to 0) (there is constant power to the radio, so I assume it's the canbus not activating the radio)
- No chimes from the chime module- even if I leave the headlights on or the key in the ignition when the door is open, etc.
- Only codes are P0036 and P0141, but I've had these O2 sensor codes for a few weeks so I believe them to be unrelated
- I can not read codes or scan once the gauges drop out, it seems like the communications just all shut down

I think this has to do with the canbus system, but I'm still fairly new to this and have no idea how to diagnose/repair/anything this system.

I'd appreciate any guesses/leads/information/insults.

-Bob C.

[Scottydoggs]

you change the battery yet? or replace the alt? whys the battery dead?

cars dont like to perform right when they have less then 12 volts. so you jump it, its got the other cars power, you take the cables off volts drop, car acts up. sound about right?

[bobc455]

New alternator about 3 weeks ago, new battery about 1-1/2 weeks ago.

I have driven the car about 125 miles (with no gauges) and I'm quite sure that the battery is fully charged now. Battery is not "always dead".

It was a jump start from AAA, and the guy was one of the biggest meatheads I've ever experienced. If you want I can PM you why the jump start was so crapfully done, but I am trying to figure out what the problem is now. I would rather keep this thread on topic, because I need to learn more about what could be causing this problem.

I'm trying to get a video to youtube.

[Scottydoggs]

so its been starting just fine since the new battery and alt?

the jump start via the meat head, just what did he do?

[bobc455]

I will send you a PM about the jumpstart.

Yes it starts just fine otherwise.

[Scottydoggs]

you should just post what he did here, it may have something to do with it.

all hvac fan speeds work? head lights all work like they should?

[bobc455]

Fan speeds work fine, heat works fine, all lights work fine.

In a nutshell, the AAA guy hooked up the portable-jumpstarter and immediately started hitting the key over and over and over. Of course with a totally dead battery it won't have enough voltage to start right away, so the solenoid was clicking like crazy (and sending plenty of voltage spikes through the system). He probably tried to start it 15-20 times before I finally ripped him away from the car and forced him to let the battery charge for a while.

[Scottydoggs]

well hes a moron but i dont think thats the issue.

off the wall but check the grounds on the trans bell housing. one maybe loose or broken off.

[industrialfish]

These exact symptoms have happened to multiple people all over the internet and so far and no one has ever found a cause or solution other than unhooking the battery or unplugging the device causing the failure. You don't have anything plugged into the OBDII port do you? Note that if you have TCS&ABS those are not working either, so drive appropriately.

[bobc455]

I have tried unhooking the battery for about 15 minutes, that hasn't seemed to help.

I don't have anything plugged into the OBDII port, except when I tried to pull codes and scan... but not while driving.

I know very little about this whole "canbus" thing, but it smells like that is the root of my problem.

Could replacing the PCM help? Or is the canbus system a separate entity? Any other clues which device might be causing the failure, so I could try unpluggin it?

[industrialfish]

I don't think PCM, or you'd probably have drivability issues. Possibly BCM though?

[bobc455]

Video of the gauges dying.

Fast forward to 1:45 for all of the excitement.

https://www.youtube.com/watch?v=51SYdVkZVD8

[bobc455]

If it is the BCM, it seems like it is working for some reason then decides to shut down. Just a guess, of course, I'm kinda clueless about this part of the car.

[industrialfish]

Wow, that takes awhile, wonder if something is overheating? When mine does it, it does it almost immediately after starting.

[Timing]

Its the battery, there are defective batteries on my shelf all the time. If it was the alt then it would atleast be ok untill the battery completely died out. This has happened on my 04 multiple times. Unless as stated you have ****ty connections( check pos and neg to starter, frame, and trans)

[REDCRAPGP]

Yea not sure why haven't had your battery and alternator tested yet you might be surprised


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[bobc455]

Ginseng and redcomg-

If the car is running and voltage is fine, why would the gauges, etc., die all of the sudden like that? Voltage doesn't drop when the gauges die.

Besides, in the past I've driven with a dead alternator before and the gauges were working fine then so I'm sure that even if voltage dipped into the 11's that wouldn't be a problem. So they shouldn't be a problem with the voltage in the mid-14's.

[HighOctaneRacing]

check all of your fuses?

[bobc455]

HOR- actually I did. But what fuse / circuit are you thinking of? How could a fuse "heal" itself when I re-start the car every time?

[nik12937]

I've had it happen, the fuse only partially blew and would hold current for 5-20 minutes at most. Check the fuses with a multimeter, the back of the fuse where the rating is written has a piece of metal exposed for either side so it can be tested without removal. A fuse can look fine but still test bad.

The fact that you recently replaced the alternator and battery and needed a jump afterwards points to a charging system issue. After checking fuses, check and clean common grounds and inspect for damaged wiring. Jumping a car can cause issues, but in many cases the issue is what warranted the jump in the first place.