Strange problem

free_couch

New Member
Feb 12, 2009
29
0
0
Sacramento, California
I have a 86.5 supra, and I noticed that when I use my turn signals, the battery volt gauge moves in sync with the blinkers. The headlights also make the volt gauge move. I thought that it might be a weak alternator, but then I noticed that when I use the hazard lights, both the tachometer and the volt gauge move in sync with the lights. So I'm thinking I have a bad ground, but I'm not sure where to start. Instrument panel, turn signals? Any input would be great.
Thanks
 

mtmk950

New Member
Feb 12, 2009
2
0
0
New Orleans, LA
free_couch;1247492 said:
I have a 86.5 supra, and I noticed that when I use my turn signals, the battery volt gauge moves in sync with the blinkers. The headlights also make the volt gauge move. I thought that it might be a weak alternator, but then I noticed that when I use the hazard lights, both the tachometer and the volt gauge move in sync with the lights. So I'm thinking I have a bad ground, but I'm not sure where to start. Instrument panel, turn signals? Any input would be great.
Thanks

I would start with getting the battery and alt tested first. The big parts stores will check them for free but they will have to be removed from the vehicle. This would be the simplest starting point before trying to find a lose ground.
 

Vector89T

stickerdave.com
Aug 21, 2005
51
0
6
45
Lafayette, LA
AS mtmk50 said, Have your battery and alternator tested. Most large chain automotive parts stores will do this for free. The battery and alternator are pretty easy to get out of a MKIII.

As for grounds, check the cables on the battery terminal. Also check the terminal itself. If you've got a factory one, or one of those generic replacements, sometimes they work loose, corrode, etc...

Check the wires that are in the battery terminals for corrosion. I don't know if it's a common problem, but on mine, I had corrosion in the ground wires a few inches into the wire. I ended up replacing them all.

I had similar problems with my '89 MKIII Turbo and ended up replacing the grounds that ran from the battery to the chassis and block with a heavier gauge higher quality wire. You can never have too much ground. I also ended up replacing the wires from the alternator to the battery's positive side as they were problematic as well in my car.

Good luck.