Charge Light Weirdness

PAguy
Club4AG Regular
Posts: 19
Joined: Thu Jul 02, 2015 12:25 pm
Location: Western PA

Charge Light Weirdness

Postby PAguy » Thu Mar 02, 2017 5:04 pm

When I turn the key on without starting, all dash lights illuminate normally.
Last week, my alternator belt broke, but I did NOT get anything on the dash - no battery light, no brake light.
Almost stranded me in a rainstorm with my headlights and wipers on. Any ideas what to look for???
1985 GTS coupe.
Thanks!
Western PA
Long string of old Toyota's over the decades.
Currently daily an '84 SR5 hatch, an '85 GT-S coupe and a 91 FJ80.
Daughter #3 has an '86 MR2.

aukword1
Club4AG Expert
Posts: 485
Joined: Fri Dec 06, 2013 6:03 pm

Re: Charge Light Weirdness

Postby aukword1 » Thu Mar 02, 2017 6:28 pm

Definitely sounds like a wiring issue since we know the bulb works. Try searching the forums for wiring diagrams, i know jondee has done quite a few and see if you have any shorts and what not. Do the usual and check fuses but maybe someone who has had this issue before will chime in with a definitive answer. I dont know enough about the wiring to give you a for sure answer.

PAguy
Club4AG Regular
Posts: 19
Joined: Thu Jul 02, 2015 12:25 pm
Location: Western PA

Re: Charge Light Weirdness

Postby PAguy » Fri Mar 03, 2017 5:22 am

ImageI have the MR2 wiring diagram.
The charge fuse is good. That would have been an easy fix.
The parking brake switch isn't wired in. But the brake light does come on if the brake fluid level is low (when I pull off the lid).
Western PA
Long string of old Toyota's over the decades.
Currently daily an '84 SR5 hatch, an '85 GT-S coupe and a 91 FJ80.
Daughter #3 has an '86 MR2.

PAguy
Club4AG Regular
Posts: 19
Joined: Thu Jul 02, 2015 12:25 pm
Location: Western PA

Re: Charge Light Weirdness

Postby PAguy » Fri Mar 03, 2017 6:23 am

The brake light must get voltage because the brake fluid sensor will fire it.
If the GTS is wired like the MR2, the only other way the light can come on is by grounding through the alternator via the charge fuse.
Unfortunately, I don't know how the alternator is wired to decide when to ground the L terminal.
Guess I can check for continuity between the fuse and the bare alternator terminal.
Western PA
Long string of old Toyota's over the decades.
Currently daily an '84 SR5 hatch, an '85 GT-S coupe and a 91 FJ80.
Daughter #3 has an '86 MR2.

aukword1
Club4AG Expert
Posts: 485
Joined: Fri Dec 06, 2013 6:03 pm

Re: Charge Light Weirdness

Postby aukword1 » Fri Mar 03, 2017 7:41 am

Here is JonDee's post on alternator wiring...

http://club4ag.com/forums/viewtopic.php?t=11437

It sounds like your dash wiring is fine and the fuses are fine. I would definitely start with checking the alternator wiring to the fuse. If you still can't get it, please let us know!

aukword1
Club4AG Expert
Posts: 485
Joined: Fri Dec 06, 2013 6:03 pm

Re: Charge Light Weirdness

Postby aukword1 » Fri Mar 03, 2017 7:52 am

http://www.toymods.org.au/forums/thread ... 4age/page3 Also might be of help. Apparently the "L" is what grounds the dash light. I'd start by checking that.

PAguy
Club4AG Regular
Posts: 19
Joined: Thu Jul 02, 2015 12:25 pm
Location: Western PA

Re: Charge Light Weirdness

Postby PAguy » Fri Mar 03, 2017 10:42 am

Hey thanks! Based on the drawing in the MR2 Green book, I thought the L terminal was the lone (battery charging) line!
So my no connectivity diagnosis is a good thing. Now I get to try the L terminal inside the plug...

It's too stinking cold out there. This has to wait a few days. I'll drive the Landcruiser for a while.
Western PA
Long string of old Toyota's over the decades.
Currently daily an '84 SR5 hatch, an '85 GT-S coupe and a 91 FJ80.
Daughter #3 has an '86 MR2.

aukword1
Club4AG Expert
Posts: 485
Joined: Fri Dec 06, 2013 6:03 pm

Re: Charge Light Weirdness

Postby aukword1 » Fri Mar 03, 2017 11:21 am

I have the ae86 factory service manual at home, I can e-mail it to you if you like. Just pm me with your e-mail and I will send it later.