Electrical Short

primo · 08-07-2010, 01:45 AM

I have a problem with my 85 Supra that I will try to narrow down all events for. The car is 100% stock, 190k miles.
1.New battery as of 2 months ago
2.replaced fan clutch, belt is separate from alternator. System ran fine, sat for a day, ran fine on way to gas up.
3. After gas up, attempted start and whole system died. No clicks, no wimpy grinds, nothing. No lights on dash, no power anywhere. Looked for smoke and smelled for it, nothing seen or sensed.
4. Sat for half hour, tried again, no power anywhere. Did my wires fry? I looked, smelled, saw nothing smelled nothing.
5. Stop laughing this is absolutely serious ...
6. Called nearest buddy who came out in 15 mins - he's mine, you can't borrow him. At the instant that he laid his jumper lead on my battery all life returned, full 12-13 volts. The car started instantly. Hmm.
7. I tried turning on the lights - ding, all power ended, car dead. No power, lights, clicks, ... nothing.
8. Buddy touched the lead on neg again and all life returned. This time, I kept the lights off. I tried rolling windows down, and this affected the voltage reading which went up, not down. Hmm, shorting? Bad ground?
9. I thanked buddy appropriately and drove off. I noticed that as the rpm reached 3k it began to sputter. Hmm, I kept lights off, radio off, windows untouched, and all special accessories off. I also kept the rpms below 3k. It drove fine for my 60 mile ride back home - mostly freeway.
10. At home tested actions in 7 and 8 which repeated exactly. I have a new battery. None of my wires are smoked. I thought maybe I lost my voltage regulator in my alternator.
11. Removed alternator and took it to Checker auto who had a load tester there. The alternator tested fine at 15.4 max volts. All tests passed.
12. The wiring has a number of "link fuses" all which appear to be normally old looking, none burned or misshapen.
13. Is this the result of a bad ground? burned link fuse/s? still the alternator is at fault? I can voltage test anything, but I don't know what I should read at any point on the bus/wire.

08-07-2010, 01:45 AM	#1
primo Stock Join Date: Aug 2010 Location: Utah Posts: 2	Electrical Short I have a problem with my 85 Supra that I will try to narrow down all events for. The car is 100% stock, 190k miles. 1.New battery as of 2 months ago 2.replaced fan clutch, belt is separate from alternator. System ran fine, sat for a day, ran fine on way to gas up. 3. After gas up, attempted start and whole system died. No clicks, no wimpy grinds, nothing. No lights on dash, no power anywhere. Looked for smoke and smelled for it, nothing seen or sensed. 4. Sat for half hour, tried again, no power anywhere. Did my wires fry? I looked, smelled, saw nothing smelled nothing. 5. Stop laughing this is absolutely serious ... 6. Called nearest buddy who came out in 15 mins - he's mine, you can't borrow him. At the instant that he laid his jumper lead on my battery all life returned, full 12-13 volts. The car started instantly. Hmm. 7. I tried turning on the lights - ding, all power ended, car dead. No power, lights, clicks, ... nothing. 8. Buddy touched the lead on neg again and all life returned. This time, I kept the lights off. I tried rolling windows down, and this affected the voltage reading which went up, not down. Hmm, shorting? Bad ground? 9. I thanked buddy appropriately and drove off. I noticed that as the rpm reached 3k it began to sputter. Hmm, I kept lights off, radio off, windows untouched, and all special accessories off. I also kept the rpms below 3k. It drove fine for my 60 mile ride back home - mostly freeway. 10. At home tested actions in 7 and 8 which repeated exactly. I have a new battery. None of my wires are smoked. I thought maybe I lost my voltage regulator in my alternator. 11. Removed alternator and took it to Checker auto who had a load tester there. The alternator tested fine at 15.4 max volts. All tests passed. 12. The wiring has a number of "link fuses" all which appear to be normally old looking, none burned or misshapen. 13. Is this the result of a bad ground? burned link fuse/s? still the alternator is at fault? I can voltage test anything, but I don't know what I should read at any point on the bus/wire.