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Discussion Starter #1
I have been working heavly on my car since i got it back from being in a shop for 7 years.
anyways follow me on IG ItalianJapanese

ok..
Last night i did a engine oil flush
coolant flush
and also fixed the rusted ass fuel sending unit that was stuck.
I got it to work

I did take the maf off and start the car to move it. Ran like shit but just needed to move it while i was cleaning the K&N filter.

After puting everything back on and making sure evverything is pluged up my lights are on while the car is running..

Coolant light temp is on even though the coolant temp gauge is working cause its showing up on my dash and its perfect
Battery light on but the alt is charging it at 13.5v
and the brake light is on but everything seems to be ok..
Car runs great but wtf! why are all the lights on.
The check engine light is off but thats because the bulb is broken. LOLOL

Btw there is also a giant exhaust leak but the lights werent on before...

idk

What are your ideas.
 

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battery light and brake light on at the same time is classic alternator failure symptom, try checking the car after its warmed up when idle drops to 800 ish rpm and see if its still producing better than 13V. Although rare I've had a alternator fail going the other way (overcharge) look for off idle (3000 rpm+) charging over 15.5V or so. Mine went to over 18V (lights got really bright, scared the hell out of me..)

wiring, and grounds after that...

will
 

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Might be a good time to do the Camry/ES alternator upgrade by picking up a used one on eBay. OEMs tend to last quite a while.
 

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Just buy the reman/new camry one. Direct plug and play. The parts store won't even know your core isn't the same :p
Not plug and play. On the 82, you need to solder on an 84/85 plug and then do the charge light mod.
 

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Discussion Starter #8
Thank for for helping me out everyone.
Been so long working on this car I forgot a lot of things.
I did do the research for upgraded the altenator and it looks like a great idea but i dont trust myself doing the diode thingy mabob to the realy to trick the battery light from coming on.
So i called Autozone this morning and they have one in stock in Hawaii for only 69.99! its reman and thats good enough for me!


When I swap out the motor for a 2jzgte I will definetly do that light trick but as of now I think this will do.
 

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Just make sure you don't expect it to last long. The same alternator is $30 on rock auto. Can't expect much for that.
 

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Discussion Starter #10
well i put in the new alternator and guess what. it doesnt work..
welll so I thought.
This car is kicking my ass.
I brought the alt back to autozone and had them test it in the machine. and it passed! twice!
SO WHAT THE HELL!
I went back home
double checked all the wiring and plugs..
12v reading from main source
and 12v reading from the plug on all 3 holes..think 1 was ground (when car ignition is on)
Anyway!
WTH
i chcked the 7.5 amp fuse.. perfect!
I made sure all the lines were ok.
IDK!
my head hurts
 

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12 V at idle and about 14 at high revs
 

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Discussion Starter #12
does not charge at all...
Im not sure whats going on rite now...

i doubles checked evreything.
the plug with 3 wires 2 black 1 whitish
2 black was giving me a positive charge and the white one was acting like a ground.

so im guessing that its all working fine.
im gonna check the relay underneath the dash but if the battery light comes on and brake light im guesing the relay is fine.

I am so bewildered
 

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yeah the 82s have that big dumb charge relay, and it can fail. PITA to find a replacement for too.

Negatory about 12v at idle. A healthy working alternator should still put out at least 14.0v at idle when the car is running and the battery is healthy and fully charged. You shouldn't see more then 14.4v at any RPM. If you only see 12v at idle, your alt is not working (though in your case with a new alt and 82, the charge relay is suspect).
 

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I'm sure you could convert the car's wiring to the later style so you could run the later alternators and charge lights. I thought there was some info on doing something similar to that here? Or just look at the 2 wiring diagrams back to back and figure it out if you're decent with wiring. Worst case, a full chassis harness from a later car would do it lol.
 

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Charge light mod with a new alternator.
Don't be put off my doing the diode mod. There are a lot of words on the mod that can be summarized as remove relay and insert diode. If you can solder the blade ends on to the diode then you can do the mod easily.
 

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Reasons for not charging: Bad battery, as in battery is fried and won't take a charge. Bad cables, cables are broken or grounded out. Bad alternator.
If you look at the wiring diagram the White output wire of the alternator goes to the battery, this is the lone wire that goes on the post. The Yellow wire is what is telling the dash light to light up on Low voltage.
Do a continuity check on your wires. Specifically the yellow wire in the plug to the charge light relay. It will be the one that is horizontal when the other two are vertical on the alternator plug and the EWD doesn't give me the exact pin on the charge light relay but one of them should give you a tone.
I did read that you checked all wires and they are ok. So this advice may just be a repeat of what you already did.
You got correct readings on the plug. 2 black will be 12v+ and the white-ish, that I am calling yellow, would be grounded.
With a failing relay it should still be charging ok. The yellow wire will still go to ground just the lights would be on when they are not supposed to.
Only having 12v at idle is a little hard to explain you should have more. Is it 12v or more like high 12s?

Someone with more electrical knowledge than me would need to speak to if the charge light mod would do anything if you don't also swap out for a newer alternator.

This is from my 83 EWD should be the same though.

13802
 

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so you're running a factory alternator for an 82? No mod needed then, but like I said, the charge relay can fail, and you will have the symptoms you have currently. I think you need to either fully do the mod and run a newer style alternator, or undo the mod you did and you probably need to replace the charge relay.
 

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Discussion Starter #20
Thank you for everyones help
I really appreciate it
I will re check all my connections and recheck everything.

When the car is running the output of the alternator is less then when the car was off.
absolutely 0 charge.

I checked the alternator twice out of the car on a alternator testing machine
I also checked the battery under load with a machine also. (will buy a new one for peace of mind)
Changed all relays and fuses touching the wiring diagram
I did the diode trick to see if it will charge and still wont. Checking output from main source on alternator and nothing
Put back in the charge lamp relay so its bascially like stock.
The only thing that is not new is the battery and charge lamp relay. ( i cant find a charge lamp relay for a 82 supra for the life of me..)
I also redid the gauge cluster lights. changed every single bulb inside the cluster and polished the front. Look friken brandnew now.

Will keep everyone updated...
ahhh these 38 year old cars.. LOL
 
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