gto400no1

iTrader: (5)

Never seen this before. Yesterday I'm backing my car in the driveway and notice when I press the brake my consol lights dim. It was daytime, lights were off, even the independently wired fogs were off as well. So I wondered if the brake lights were dim, put a weight on the brake peddle and took a look, seemed to be usual brightness. So it was just the consol lights. Ok maybe it's a ground issue. One last test. I turn on the headlights then off. Try the brake and everything is fine, no longer dimming when pressing the brake. Any ideas what this was? Would a going bad stalk do this? Also want to point out my grounds are pretty good, have fixed a few since I got the car. I don't even get dimming with the subs are blasting and hitting window switches.
Thanks guys.

njmaxseltd

iTrader: (19)

I've been having a similar issue. The dimming or brief noticable dim when I press the brake just after the car's been started. I'm also getting a slow crank from time to time. Last night the car was completely dead when I got back to it in the Walmart parking lot. All I did was play with the main battery cable and everything came back to life. Very quick cranks are back and no dimming at all. I suspect a poor connection on that main positive battery cable. I see two connectors that run off of it, I'm sure one probably goes to the alty and the other must supply power to main accessories.

I'm going to take that harness out today and verfy that all the connections are clean and follow the two main sub wires to their sources and make sure that's all in good shape as well.

Grounds arn't an issue as when this started happening I installed a grounding kit and cleaned all the mian ground connections. The battery is only a month old too and their is no corrosion on the mian terminals.

I'll post up my findings later on.

Swazey

i was in 2 hours of traffic over the weekend and noticed that when i hit the brake pedal my voltmeter (which is hooked up to my alternator), would drop about 0.5 volts for a split second then jump back up - everytime i hit the brakes. If i held the brakes there was no change. This also happens if hold the window switch up while the windows are rolled up. there is a slight decrease in volts for a split second causing lights to dim.

i do have a powerful sound system as well which dims my lights and every time i have it turned up and the bass hits, my volts drop by 2 and you can really see my lights dim. this is only because i do not have a capacitor or farad cap.

i'm also interested in knowing why this would happen. i have added 3 ground wires and checked all my grounds so i do not think grounding is the issue.

njmaxseltd

iTrader: (19)

Swazey - Seems normal to me.

UPDATE: I took apart the main battery harness last night. There are two sub harnesses that are plugged into the main harness right by the bettery terminal. They look like RJ45 jacks, with only one large terminal in each. One connection had some black burnt spots on it. I used some sand paper to clean off both sides in every connection. I cleaned them with brake cleaner then lubbed them up with Lithium grease. I also tried to uncrimp the main wire, but was unable to get it open. There is another smaller connector that's taped onto the main harness, I opened that up and cleaned & lubbed it as well. So far so good, no dimming and nice fast cranks this morning. We'll see how long this "service" lasts and if the problem comes back. If it does, I'm going to replace the (+) main battery harness.

gto400no1

iTrader: (5)

Interesting, might have to take a look into mine just for preventative maintenance.

Also have an update on my situation as well. So basically as I mentioned when I turned on the headlights, then turned them off the dimming issue went away. Day later I'm leaving the office and notice that I have no taillights. So obviously check the fuse and it's blow. I replace it and everything seems fine for a few days. Today same issue happens, dimming when I press the brakes. So I listen when I turn on the headlight and I hear the fuse blow. Long story short dismantle the trunk looking for a short. even went so far as to remove the trailer hitch harness since I found it sitting in a pool of water in the spare tire well (wasn't aware of leak, another days problem - did drain it of course). After checking every wire, out of dumb luck stumble across my bulb having a short. Now mind you, it lights up fine when I press brake, but when I turn on the lights, fuse blows. I've never seen anything like this. Have any of you?


Picture doesn't quite do it justice, but the filaments are all twisted and of course touching.

njmaxseltd

iTrader: (19)

Thats very interesting...

VQ30MPG

I've seen bulbs deform internally before, but never to that point. Congratulations, looks like you've found the source of your problem.