What's wrong with my electrical system.
09-15-2002, 10:02 PM
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What's wrong with my electrical system.
Well, I bought my 85 911 Turbo Look Carrera about 1 year ago. One problem I have had with it as soon as I got it is a notchy tach. It would get to about 4000 then stop for a second then swing really quick to 6000.
I figured my alternator was going bad.
In the last 4 moths every time I went to drive the battery was allways dead. I would hook up my battery charger to the battery while it was still in the car conected and charge for about 10 min the start it up with the assist of the charger.
1 month ago I go to drive and do the normal routine. Well, this time I turn on the lights and the car dies. I would charge up then die.
I figured it was time to replace the battery and/or alternator. I had the battery tested and they told me it's fine. I was not sure about that then or now.
I took the alternator off and had it rebuilt. Yes the diodes were replaced as well.
I put in in and disconected the battery from the car, let the battery charge and the car starts with otu the assist of the charger running. I let it run for 5 min then turned it off. I go back to the car about 1 hour later and the car is dead. I was pretty angry by now and I pulled out the old charger and with the battery still conected I use it to help the car start (could this of destroyed the diodes?) I let it run for a few miniutes then turned it off. Started back up and run's fine. Did it once more and it was fine.
Well, I pull the car out and drive around. Drove for 5 min to parts store for fuses for AC, car was off for 5 min, got in and drove some more. It was great. Drove for about 10 miniutes and stoped to get gas. Started back up and no problem, drove over to my grandmother home, turned off the car and there it was!
BATTERY LIGHT IS ON WHEN KEY IS OUT OF THE IGNITION AND EVERY THING IS OFF!
I left then drove around for about 1 hour. Car runs good (still has the weird tach) I turned it off for a few seconds and the car starts back up fine but when key is off the light is still on. Car runs good with AC blowing, and radio playing loud and lights on.
I got home about 30 min ago, I am going to try to start the car after it has sat for 1 hour.
Think my battery is just bad or going bad. Did my using the charger to assist starting the car fry a new alternator? Any other ideas?
I figured my alternator was going bad.
In the last 4 moths every time I went to drive the battery was allways dead. I would hook up my battery charger to the battery while it was still in the car conected and charge for about 10 min the start it up with the assist of the charger.
1 month ago I go to drive and do the normal routine. Well, this time I turn on the lights and the car dies. I would charge up then die.
I figured it was time to replace the battery and/or alternator. I had the battery tested and they told me it's fine. I was not sure about that then or now.
I took the alternator off and had it rebuilt. Yes the diodes were replaced as well.
I put in in and disconected the battery from the car, let the battery charge and the car starts with otu the assist of the charger running. I let it run for 5 min then turned it off. I go back to the car about 1 hour later and the car is dead. I was pretty angry by now and I pulled out the old charger and with the battery still conected I use it to help the car start (could this of destroyed the diodes?) I let it run for a few miniutes then turned it off. Started back up and run's fine. Did it once more and it was fine.
Well, I pull the car out and drive around. Drove for 5 min to parts store for fuses for AC, car was off for 5 min, got in and drove some more. It was great. Drove for about 10 miniutes and stoped to get gas. Started back up and no problem, drove over to my grandmother home, turned off the car and there it was!
BATTERY LIGHT IS ON WHEN KEY IS OUT OF THE IGNITION AND EVERY THING IS OFF!
I left then drove around for about 1 hour. Car runs good (still has the weird tach) I turned it off for a few seconds and the car starts back up fine but when key is off the light is still on. Car runs good with AC blowing, and radio playing loud and lights on.
I got home about 30 min ago, I am going to try to start the car after it has sat for 1 hour.
Think my battery is just bad or going bad. Did my using the charger to assist starting the car fry a new alternator? Any other ideas?
09-15-2002, 11:41 PM
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45 miniutes later I tried again.
The car was reading 6.5 volts when off.
I started it and it dropped to 5.9, then about 5 min later it was at 5.2.
I killed the car then it was at 4.7
I tried to start and nothing.
Light was still on the whole time. I am thinking th battery just wont hold charge but I am asking becuase I dont want to go buy parts that I will have no use for. My 101 projects book says the lamp being on when car is off indicates a dead alternator, but how can that be when I just replaced it. I checked the ground strap and it looked fine.
The car was reading 6.5 volts when off.
I started it and it dropped to 5.9, then about 5 min later it was at 5.2.
I killed the car then it was at 4.7
I tried to start and nothing.
Light was still on the whole time. I am thinking th battery just wont hold charge but I am asking becuase I dont want to go buy parts that I will have no use for. My 101 projects book says the lamp being on when car is off indicates a dead alternator, but how can that be when I just replaced it. I checked the ground strap and it looked fine.
09-16-2002, 04:21 AM
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1) Check out your battery and tranny ground straps.
2) I've got to believe that the battery light being on when the ignition is shut down is either a diode problem or caused by back circuits from a poor ground connection.
3)There's a good possibility that something is draining the battery (Example: glove box lite or hood lite on all the time). Normally the only thing drawing any current with ignition off would be your radio presets.
4) If you have a meter that can measure milliamps
--try removing the POS battery cable and with the meter on it's highest milliamp setting, connect it between the POS batt. terminal and the cable with the ignition OFF. The meter will indicate the amount of current draw you're having in that static condition. If you find any sizeable drain then you'll have to start popping fuses to determine what circuit is causing the problem.
Good Luck! A little time consuming but they're fun
to chase down!
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
2) I've got to believe that the battery light being on when the ignition is shut down is either a diode problem or caused by back circuits from a poor ground connection.
3)There's a good possibility that something is draining the battery (Example: glove box lite or hood lite on all the time). Normally the only thing drawing any current with ignition off would be your radio presets.
4) If you have a meter that can measure milliamps
--try removing the POS battery cable and with the meter on it's highest milliamp setting, connect it between the POS batt. terminal and the cable with the ignition OFF. The meter will indicate the amount of current draw you're having in that static condition. If you find any sizeable drain then you'll have to start popping fuses to determine what circuit is causing the problem.
Good Luck! A little time consuming but they're fun
to chase down!
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
09-16-2002, 10:56 AM
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I'll check to see if it is draining this afternoon.
I am willing to wager this new rebuilt unit is dead, if so the shop has a 30 day garente on parts and labor so I will just get a new one free of charge.
I will also check the grounds once more.
What could cause on to fail so quickly? I took a picture of the wiring before I removed the wires and I rewired everything just as it has been.
One thing was when I used the charger to help jump the car I conected both the + and - to the battery DOH! ouch:
. But it was doing fine even after that and the light did not come on till later.
I am willing to wager this new rebuilt unit is dead, if so the shop has a 30 day garente on parts and labor so I will just get a new one free of charge.
I will also check the grounds once more.
What could cause on to fail so quickly? I took a picture of the wiring before I removed the wires and I rewired everything just as it has been.
One thing was when I used the charger to help jump the car I conected both the + and - to the battery DOH! ouch:
. But it was doing fine even after that and the light did not come on till later.
09-17-2002, 03:05 AM
#6
I can't imagine the battery being cycled that many times being OK still, especially after 4+ months of that. Load tested or not, just for the sake of the price of an alternator, I'd replace it. Check the conditions of your clamps, if they're not holding tension, change them and clean & coat your ground connections with Lithium at the point where it conncets to the body underhood. It's all cheap stuff, and you'll never know what's going down until you're sure those are all OK. And, it's probably time anyhow.
rjp
rjp