Electrical problem in the rain this morning

[quangtran89]

So this morning when I turn on my car everything was fine. Then suddenly 4 miles down the road one of my headlight turn off on my then 10 minutes later the other one turn. As I was driving I also notice that all the light on dash board were getting dimmer and dimmer. Also headunit went out on me. There was no power to it at all, It couldn't even come on standby.

After driving with my lights off for 10 minutes in the dark, I turn back on my headlights and everything is fine....


These two light have used to appear but go ago after driving for about 10 to 15 mintues, but they are always.

My battery is 3 months old and my HID are 35w.

Anyone know what could have cause this problem?
Thanks

[AlmightyCamry777]

Some possible causes:
bad ground (check your battery negative strap at both ends for tight connections).
Loose alternator belt.
Dying alternator.
Ignition switch going bad (do you carry a lot of keys? This can wear out an ignition switch prematurely).

[l0ll00l]

I can't positively say that you are experiencing the same issue as I did yesterday(in the rain), but after driving through a couple puddles while turning the tires, I had the same issue. +

My gauge lights dimmed, headlights dimmed, A/C blower motor slowed down, and head unit lights dimmed. My initial thinking was that my belt was wet, so I pulled over, put the car in neutral, and revved the engine a little. After a couple revs, the belt squeaked a little, and the electronics all came back on.
The immediate problem was obviously a wet belt, but I'm thinking I may also check tension this afternoon.

You said the battery was relatively new, so Almighty's suggestions seem right on the money. In my case, I know I have a bad battery, so that's probably why mine dimmed so badly when the alternator wasn't working.

Actually, after re-reading what you wrote, is it possible that something in the HID kit you installed is shorting out, causing these electrical issues?

[quangtran89]

Thanks for the quick reply guys. I'll start checking those possible causes.
My HID ballast went bad after the first month so I sent them back and got a new set. It could be possible that there's something wrong with this ballast as well.

[rusty9]

a burnt out alternator will put out some amps while revving, but practically nothing while idling.

[quangtran89]

So I unplug the negative on the battery while the car was running and it seem fine.
I also notice this.

[Mike Gerber]

Originally Posted by quangtran89

So I unplug the negative on the battery while the car was running and it seem fine.
I also notice this.

Don't unplug the battery terminals while the car is running. This was a valid test on cars years ago (I did it myself many times) but should not be used today. You risk ruining some of the sophisticated electronic components on todays cars by the voltage spikes caused by doing this.

The plastic cover in your picture is just that, a plastic cover that covers where the postive cable from the battery attaches to the alternator. Cover it with some electrical tape temporarily or spread some of that stuff that is used as a brush on insulator over it.

All that said, I think you have a loose alternator belt or a bad alternator. Charge your batttery from an external source and then take your car to one of the auto parts stores in your area that offers free testing of the charging system, with the alternator still on the car. Make a few phone calls to auto parts stores in your area and ask if they offer this free service. If it is a defective alternator you have a few options. 1. Replace it with a new Toyota unit, which will be very expensive. Around $550-$600 for the part. 2. Replace it with an off the shelf rebuilt unit from your auto parts store. The rebuilt unit will run about $150 for the part. 3. Find a local auto electrical rebuilder in your area and have them rebuild your existing unit. That will cost you $125-$150. The last one is the choice I prefer.

Good luck.

Mike

[quangtran89]

Thanks for help everyone. I will test the alternator tomorrow to see if I need a new one. I just tighten the belt few minutes ago.

[Mike Gerber]

"I just tighten the belt few minutes ago."

Was it loose?

Mike

[quangtran89]

It was slightly loose.

[quangtran89]

The problem came back. I cover that positive wire from the battery on the alternator and the tape melted. I will be taking off my alternator and getting it test today.

[Mike Gerber]

Originally Posted by quangtran89

The problem came back. I cover that positive wire from the battery on the alternator and the tape melted. I will be taking off my alternator and getting it test today.

"I cover that positive wire from the battery on the alternator and the tape melted." Sounds like that alternator got very hot. Having that alternator checked is the right thing to do. There are some auto parts stores that can check the alternator right on the car. Call around to a few auto parts stores in your area and ask if they offer this free service.

Mike

[quangtran89]

I had autozone tested my alternator and the test said that charging system need repair. So I bought a new alternator and replace it. Everything seem to be normal so far. Both lights on the dash are gone. Wish I made a DIY. Replacing the alternator was very easy.