Car: 1995 SC400 120k miles

Symptoms:
Headlights Dim when hitting the brakes intermittently and turn signal activation making the dash/radio/climate control flicker for a second and back to normal.

Also the yellow light for tailights being out is on, when I put in brand new bulbs all around a week ago. Visually they all work.

Replaced Battery one month ago
Terminals
Alternator when car first bought (a few months ago)
Also re-did power steering

It only happens after a few miles of driving, and randomly.

Well I've searched, and searched, and searched more and have come to the conclusion that it is a bad ground somewhere.

And got to the point of needing to check all of the major ground points, but I'm a newb when it's coming to diagnosing electrical problems, Does anyone know EXACTLY where the location of the ground points are on the car, specific location wise?

The first one I want to go with is the negative battery cable ground, but the rest of them I'll be lost on, so does anyone have a diagram or pictures of the locations?

 

its more than likely the ground cable coming off the battery.....get a new one and your head lights will dim no more.....it is screwed in underneath the car near where the oil filter is.....

 

That looks like the culprit, because the car is now hard to start, like a slow crank and start, battery is fine, not drained, so could it be high resistance in the cable?

The wires inside on cable end are green, that should be an indication right?

-Adrian

 

Yes. that green corrosion is causing a high resistance porblem. Change it!

 

Where can you buy the replacement cable you speak of here that runs from the negative terminal on the battery to the ground point near the oil filter?

I called Lexus and asked how much the wiring harness was to replace the negative and positive main electrical cables and they quoted me 3548.00 dollars saying I had to buy the entire engine wiring harness and that they don't make or sell only portions of that wiring setup.

Um - that just seems ridiculous! Sooo....please help with some info on where your getting these cables from - it would be GREATLY appreciated.

 

go to the auto parts store and ask them where they keep the battery cables.....find the thickest one you can get.....

 

Now another one has arise, I love this car

Radio and CD Changer does not work, the fuse underneath the hood keeps blowing, only thing is, everything going into the radio wiring-wise is fine (behind the physical unit), nothing broken or touching upon physical inspection.

Then followed the wires coming from the fuse box, nothing burned through up till near the firewall, in which I cannot get back there at this time.

Me and a friend think that something back there is rubbing against each other some something got burned though or melted a wire. Any second opinions or whoever had the same symptoms found a resolve for it? Everywhere I searched has no resolution follow-ups (including my problem, lol.)

Anyone else have this many electrical problems?

Brief history:
Windows do not operate (broken wire in door, fixed, windows work)
Headlights dim (corroded ground cable, fixed, I thought, but it's randomly happens again)
Brake lights randomly do not work(bulbs fine, tail light ground look sgood upon inspection)
Sunroof did not work(blown fuse, replaced with new fuse)
Installed HID's left ballast blew up, yet to receive another kit.

-Adrian

 

The radio/changer issue is being caused by a bad Nakamichi amp. Disconnect the three sets of cables to the amp. Its located in the trunk under the CD changer. After that, replace the fuse under the hood and check the radio and changer again. Good luck on finding another factory amp. You'd be better off putting an aftermarket unit in.

 

I have a stock 93 SC300 auto w/ 118k. I recently am experiencing the same symptoms as in the first post. It happened after I had the alternator/terminals replaced. Battery is 3 months old, battery terminals are about 3 weeks old, non oem alternator is about 3 weeks old, no oil leaking onto the alternator, and I cleaned off the negative battery cable to chassis ground. When I turn on the signal then brake w/ the ac on you can hear the ac blow a bit weaker. After I let go of the brake and turn off the blinker, ac seems to feel stronger. On some days when I signal or brake all the interior lights turn off then back on really quick. Alternator is still under warranty but I cannot replicate the problem as it comes and goes. Could it be that the alternator is too weak since it is a generic brand? Any other suggestions?

Edit: Also, the new battery was smaller than the oem size of 27f, but the numbers outperformed the oem one.