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Discussion Starter #1
Hello! Ive had my G8 for 4 years now and just recently my dashboard seems to go haywire when I accelerate. If I'm braking or at a stop everything is on and working. When the dash is blacked out, it seems none of my accessories work either. (Radio, AC/heat etc.) Now here's why im stumped, I recently (as in last week) had to replace the battery due to a bad cell but when my dash does come on it is throwing a "low battery" error. One other time it threw me an alternator error message as well.

I have several mechanic friends that don't know much about my car so before i go and spend my child's college fund to have some hack dig into my car, i was wondering if anyone here had the same issue.

Things you should know:
1. Car has 110k.
2. No other mechanical issues to date.
3. Fuses have been all checked.
4. Dash was going black before the battery was changed.
5. Driven daily.
 

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Check for ground wire issues
 

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Discussion Starter #4
I might also add that its worse in the morning after it has sat overnight. It will black out EVERY time I accelerate and comes right back after I'm braking a few seconds.
 

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Sounds like a ground or a loose connection somewhere for sure. Hard part is tracking it down. Good luck.
 

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Start with the ground wire on the battery. The bolt where it connects to the body is exposed outside and rusts causing a bad connection. It's an M8x1.25 bolt (about an inch long). Get a new one, and chase the threads with a tap. This fixed a number of oddball things on my car. Nothing as bad as the dash blacking out, but it's a cheap start at least.
 

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My mind says the fact that the engine continues to run, kinda says a lot of the power an ground circuits must be good. There are 20+ items that have their ground returns all going to the same grounding stud. Basically all of the items on the instrument panel, center console (upper an lower sections), the items on the headliner, and your high brake light. It says that grounding point is located behind the right side of the instrument panel, attached to the the right inner side of I/P cross beam (which still might be hard to visualize, see or find). A test might be to have your dome, reading, an sun visor lights turned on, an see if they also shutdown when the IP does. If a friend can follow you, double check what happens to the high brake light when you go dark.




added thought ----- On the power side of things---- Under the cover of the underhood fuse box, there are 2 hex screws that secure 3 connectors to the bottom of it. Those connectors carry the wiring that goes out to all the things assigned to them. Wouldn't hurt to double check those 2 screws. If a little loose, it might create an intermittent power dropout condition.
 
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