Hello,

I have a 95 4runner with seemingly unique problems. Whenever I step on the brake, use turn signals, hazards, use power anything, it causes the whole system to short and the radio to pop, lights dim, ect. Also when i would turn the car off and leave it in ACC, I would loose all power for a few seconds, up to a few minutes. This also happened after the car had been parked a few times. Checked the fuses, all in good shape. Next checked the terminals, the negative broke as soon as I took it off so I replaced it with a new beefy one and the problem disappeared. All was well until a week ago when the problem came back. My mind instantly thought of the alternator, it makes perfect sense, however I don't want to spend the money on a new one if it isnt the problem.

I'm hoping you guys will have perhaps had this issue before and know what the solution is, thanks in advance!

 

Simple to test the alternator on the vehicle with the engine running test the battery voltage.

Then put all the electrical load you would use in a normal drive.

At any time it should not drop below 12.5 VDC ideal would be in the 13VDC to 14VDC but age plays a factor at times.

 

I take a wire brush to all my ground wires and to where they connect to. Sounds like you have some corrosion that can keep from getting a good connection as well.

 

Do you have a trailer harness? Try removing all that stuff if you do. Toyota uses a floating ground to power the lighting, well everything matter fact. Ive seen those trailer harness screw things up.