86 4runner charging

[Curmudgeon]

I have been tasked with figuring out my neighbor's 86 4runner no/occasional charge issue. He has a parts store book, goes to 85. Some shop told him a control box inside the right footwell was bad. I used to work on these before the accident forced my to hang up my shop overalls.....I need to find a good schematic on this vehicle. He's had the alternator changed, no difference. I can do it cold, run the wiring, but for me always better if I have a schematic. Sometimes it works, most times it does not.
Thanks.
Dave

 

[KidVermicious]

I have been tasked with figuring out my neighbor's 86 4runner no/occasional charge issue. He has a parts store book, goes to 85. Some shop told him a control box inside the right footwell was bad. I used to work on these before the accident forced my to hang up my shop overalls.....I need to find a good schematic on this vehicle. He's had the alternator changed, no difference. I can do it cold, run the wiring, but for me always better if I have a schematic. Sometimes it works, most times it does not.
Thanks.
Dave

First thing I'd suspect if I was chasing an intermittent charge would be the ground wires. There's a link to a PDF of the factory service manuals in the stickies up top.

 

[RAD4Runner]

First thing I'd suspect if I was chasing an intermittent charge would be the ground wires. There's a link to a PDF of the factory service manuals in the stickies up top.

FSM's here:


Someone's post on Yotatech with illustration of ground locations here:

 

[fourwd1]

There's very little difference in those two years. The manual should do if it has schematics.
The EFI ECM is the control box behind the right side kick panel.
Corroded or loose connections on the battery pos or neg cables could affect charging.

 

[Curmudgeon]

Did the basics...clean terminals, alternator test and replace. Went through the sticky, all but the schematic, which is a EWD040U publication. He's had it several places, now I get to dive in and figure out what others may have done to it, then what's wrong.
Still looking...I'll look at the link provided next.
At least it's not Lucas.
Dave

 

[Footofgod]

Maybe a stupid question, but did you get the battery itself checked?

 

[Curmudgeon]

Yup...checked it. Apparently, while driving, chattering relays, and it stops charging. Driving home after dark becomes a challenge, when you have to turn off the lights to keep it running. Then, chattering of relays, and it's charging again. This is what he says....I have not had it happen to me yet.

 

[Curmudgeon]

Had some time today to look at it. No gauges at all, no indicator lights....lack of accessory power. Checked ignition switch, good. Checked the gang plug for the switch (seen them melted at one plug before), good. Checked all fuses....everything test ligh power both sides except one, nothing either side. Not uncommon with that circuit not energized.......checked on-line daigrams and book he had. Traced it out...."Engine" fues in fuse box feeds all the dead stuff. Yup, it was that fuse.
Decided to pull the fuse....had to get a pair of pliers. Apparently, he's has water leak issues, the silly fuse was so corroded it was white. Scraped the contacts cleanw ith an xacto, sprayed the socket with ZEP45, new fuse, works in all aspects now.
Dave