Hey i have an 04 G35 coupe i recently bought. When i signal left, it behaves normally. When i signal right, as the signal light blinks, the brake lights blink, and the dash and running lights dim on par with the signal light blinking. It seems to have possible aftermarket headlights and has a double din headunit with an aftermarket amp. Could i have a faulty ground somewhere? Why is my dash and climate control lights dimming with the headlights and the brake lights blinking. Thanks!!!

 

Sounds like something is draining current to ground but not enough to trip a fuse OR a ground didn't get hooked up (or is corroded) which is causing current to find another path to ground. The headlights each have a ground at the front of the wheel well, the AC controller has a ground for basically everything including the ECU right behind the right side of the AC controller.

I would START with the battery ground though, take off the big plastic cover so you can clean up where the negative wire attaches to the chassis, unbolt it, use a metal brush to clean the lug, the bolts, and the face of the chassis a little, apply electrical anti-oxidation grease (DE-OX) and reassemble to see if the problem goes away.

 

i just finished cleaning the grounds that i could see in the engine bay, still not fixed, why would a bad ground be turning tail lights, headlights, and dash lights on and off with my blinker? Also where is the ac control unit you are talking about thanks

 

That thing in the middle of the dash that has the air conditioner buttons is the AC controller. Behind it is the primary ground for the ECU and all the major dash components.

 

i have a double din deck, would that have possibly done something to the wiring? Also why would a bad ac controller ground mess with head and taillights

 

The loose ground issue is part of my second theory, my initial thought is something is draining current to ground.

If current can't take it's intended path to ground and instead has to go THROUGH other equipment to go to ground it can cause all sorts of misbehavior.

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Try moving the bulbs from the left side to the right side to see if the right side then behaves normally.
If so you may have mismatched bulbs?

You can also try measuring the resistance from the bulb ground to negative battery ground.

Telcoman

 

so i had my door locks fail, i assumed, so i took my door panel off, and pulled the actuator. Mine hasnt cone in the mail yet so today i put the bad one back in. Now none of my door locks or windows work (windows had worked just fine previouslly

 

off topic to this post but recently my door locks failed, i took the driver side out, and ended up needing my car so i had to put the door back together now no controls on either of my doors work, windows or doors. I hadnt even touched the passenger side so why isnt it working? Is my bcm bad? What other causes are there

 

Blown fuse?
Missing ground?

Telcoman

 

 

 

Dealership can do a BCM diagnostic for a reasonable price if you suspect yours is failing.

 

both sides are plugged in, the none of the windows even attempt to move, the motors worked fine so i am sure they arent dead, i even took them apart and cleaned them. I am fairly certain my door locks are gone tho and when i push the unlock button inside the door i hear a click from the bcm but nothing happens, could this and my weird signal light issue be related to the bcm going bad? What common symptoms are involved

 

Could be broken wiring in the driver door harness, ring out the wires for continuity, verify power, etc.