Topic: 1st gen charge light/electrical short suggestions needed

[jmac]

So, I think I've got a short somewhere in my '81..................I know I've got a short somewhere .  Charge idiot light used to randomly turn off and on while driving until if finally got where it stays on all the time now.  I actually saw it go off for like 10 seconds a few months ago; it was thrilling.  Anyway, it was no big deal in the Summer because it wouldn't drain the battery even over a weekend without running, but now that it's been down in the teens every night that's a different story.

Most people point at alternator, battery, voltage regulator, or relay for problems, but I don't believe these to be the case for me as it will crank up great after a cold night if I just disconnect the battery before I go to sleep.  Also factory voltage gauge indicates very good charge (well over 12).  So I'm pretty sure it's a short.

This is my daily driver so I'm really not looking to jack with the battery twice a day, and let my neighbors find out they are really living next to white trash.

Questions for the gurus:

Light stays on with all fuses out (except for "gauge" fuse).  Am I right at thinking that short is before fuse box, in the fuse box, or in the gauge circuit after the box based on this?

Will this light only come on with shorts in the charging circuit only or can there be a short anywhere causing this light to come on?

Anybody seen any particular wire(s) and/or plug-in(s) that are notorious for having problems/shorts?

Just trying to get some pointers on where to start as I'll be working in the cold on this one, and yeah, I got a multimeter.

[79coyotefrg]

probably the wires between the alt and the regulator/main harness.  Mine where badly rubbed and shorted between each other

[4x4yota]

I had the same problem with my 82  and replaced everything (alt, reg, wires) and turnded out to be the charge lamp relay so ever since then I have been stocking up on them as I find them in yards

[8D3TOY]

Not sure if this will help but a mechanic I know worked at Toyota for 20+ years and when I was having charge light combined at times with the brake light (usually but not always) he said it was emissions related, kind of like throwing a code.  I have seen guys spend huge $ replacing everything electrical when it was an O2 or something.  It sounds like you have an electrical problem to me but just keep that in mind if you cant figure it out.

[jmac [OP]]

I'm sure it's a short given the battery loosing charge overnight when connected................but still hunting around for it.  Cheap fix but time consuming.

I'll keep everyone posted when i figure it out.

thanks for the tips

[StillH2O_Toy]

Mine does the same thing.  Replace with Toyota Alt. Voltage Reg.  Battery  I think mine is the charge light relay as well, good luck.

I had the same problem with my 82  and replaced everything (alt, reg, wires) and turnded out to be the charge lamp relay so ever since then I have been stocking up on them as I find them in yards

Would you want to part with one of your spares?

[4x4yota]

Mine does the same thing.  Replace with Toyota Alt. Voltage Reg.  Battery  I think mine is the charge light relay as well, good luck.

Would you want to part with one of your spares?

pmed you