Hey guys,
Got a 92 pickup with 22re, auto. Anyway I noticed a few month backs while driving for over 30 mins the dashboard lights (battery light, brake, and at oil temp) would all light up together very randomly. They would light up all together, sometimes flashing, sometimes on dimly than bright, but all on.

So I searched online and so believed the problem to bey alternator brushes. I took my alternator off and apart, replaced the brushes with a new OEM set, and put it back together. It's been good with no lights on for a month. Even on extended drives.

So just yesterday I was driving for a longer period of time, but not that long, and all three lights came on. There was no blinking or flashing or them on dim. They were just on for a few mins, and than turned off. They haven't been on since.

I'm just wondering what could be the problem? Is there something loose electrically, or is there something wrong with my truck. I just did the alternator brushes which I know many people online said does the trick.

Any help, input or ideas would be appreciated.

Thanks in advance!

 

Refer to charging system schematic for 4Runner 22RE (might be similar to yours)



Monitor your alternator "B" output (That's the screw terminal with thick white wire).
Alternator output should range from around 13.5Volts to 14.5V. Then, "L" remains 12V.
When alternator output is outside of that range for extended time. "L" will go low and provide low voltage to negative side of battery, brake and A/T oil temp lights, causing them to light up.
If "B" output is good but 'L" goes low, probably bad alt electronics.
If "B" output is too low, hence "L" also low, check the whole charging circuit (posted here).

Good place to probe "L" output:

 

Thanks Ray, It may sound stupid, but I just learned something and never would of thought of it until I seen your picture, but that would be a great place to check on a fuse or a test point. Thanks!!!

 

RAD: Thanks for the informative reply, so I guess it's either my charging system or alternator. I have yet to test it since I don't have my multimeter. Yesterday, I did notice it happening again. I happen to pass by an Advance Auto Parts, and I know they do free testing, so I figured what the heck.

When they tested it they said my alternator was fine, made me rev the engine with all accessories on. They did say my starter wasn't cranking enough though. I've been having starting problems with this truck ever since I got it. It appears it only starts good when the engine is cold. If it's been on for a while and you turn it on and off, it will require multiple attempts for it to finally fire, kind of stumbles for a second than runs fine. I was thinking it was a fuel related issue, and had plans of replacing my fuel pump, fuel bracket, and fuel filter. But Advance Auto was saying the machine says bad starter. I even asked about the battery, and they said the battery is fine according to the machine. So I dunno

I will try to do the multimeter test soon, and see where to go from there. I was honestly hoping it was a bad alternator because that's not too expensive to replace, I fear if it's a charging system problem what I would need to do.

 

Trust the shop but verify and see for yourself find your multi-meter.

If you have trouble cranking, before replacing anything, check if your starting system is wired incorrectly BY TOYOTA like 1986 to 1988 4Runners as explained here.

Best of luck and Happy Easter.

 

Last I looked the alternator was the most expensive part of the charging system except where the ECM is considered part of the charging system.

I am willing to learn if I indeed am missing something.