electrical gremlin
Thread Starter
Pro
Joined: Sep 2006
Posts: 702
Likes: 2
From: Conyers Ga
electrical gremlin
OK gurus............I have an odd one here but first a few stats:
88 coupe
battery is just shy of 2 years old
alternator is less then a month old
car is only used on weekends
the gremlin:
After installing the new alternator I noticed that when I first start the car after it sits overnight, my dash voltage reading is 11.2 and the battery light comes on. If I run the car for about 2 minutes it climbs right back up to 13.3 which is normal. Last week I used a battery charger on it overnight but the dash still read 11.2.
This week I let the car sit for FIVE DAYS and tonight, before starting it I put my voltmeter on the battery and it read 12.9 yet the dash read 11.2 with the light coming on. It can't be a parasitic drain because after 5 days the battery should have been dead. At the vert least it shouldn't have read 12.9.
any ideas???????
88 coupe
battery is just shy of 2 years old
alternator is less then a month old
car is only used on weekends
the gremlin:
After installing the new alternator I noticed that when I first start the car after it sits overnight, my dash voltage reading is 11.2 and the battery light comes on. If I run the car for about 2 minutes it climbs right back up to 13.3 which is normal. Last week I used a battery charger on it overnight but the dash still read 11.2.
This week I let the car sit for FIVE DAYS and tonight, before starting it I put my voltmeter on the battery and it read 12.9 yet the dash read 11.2 with the light coming on. It can't be a parasitic drain because after 5 days the battery should have been dead. At the vert least it shouldn't have read 12.9.
any ideas???????
Safety Car
Joined: Jul 2004
Posts: 3,834
Likes: 30
Originally Posted by nyernga1
OK gurus............I have an odd one here but first a few stats:
88 coupe
battery is just shy of 2 years old
alternator is less then a month old
car is only used on weekends
the gremlin:
After installing the new alternator I noticed that when I first start the car after it sits overnight, my dash voltage reading is 11.2 and the battery light comes on. If I run the car for about 2 minutes it climbs right back up to 13.3 which is normal. Last week I used a battery charger on it overnight but the dash still read 11.2.
This week I let the car sit for FIVE DAYS and tonight, before starting it I put my voltmeter on the battery and it read 12.9 yet the dash read 11.2 with the light coming on. It can't be a parasitic drain because after 5 days the battery should have been dead. At the vert least it shouldn't have read 12.9.
any ideas???????
88 coupe
battery is just shy of 2 years old
alternator is less then a month old
car is only used on weekends
the gremlin:
After installing the new alternator I noticed that when I first start the car after it sits overnight, my dash voltage reading is 11.2 and the battery light comes on. If I run the car for about 2 minutes it climbs right back up to 13.3 which is normal. Last week I used a battery charger on it overnight but the dash still read 11.2.
This week I let the car sit for FIVE DAYS and tonight, before starting it I put my voltmeter on the battery and it read 12.9 yet the dash read 11.2 with the light coming on. It can't be a parasitic drain because after 5 days the battery should have been dead. At the vert least it shouldn't have read 12.9.
any ideas???????
Thread Starter
Pro
Joined: Sep 2006
Posts: 702
Likes: 2
From: Conyers Ga
Originally Posted by Da Mail Man
......remove the battery and have it load tested as it sound like there are problems..also, after you start your car, place a volt meter on the hot wire at the alternator and tell us what the voltage is...may be a bad voltage regulator....
The battery was tested under load. I will check the hot wire from the alternator tomorrow............
The one thing I didn't check. DOH!!!!!!!!!!!!!Thanks mailman....
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The dash voltmeter reads low if the engine is not running! Measure the battery teminal voltage when you start the engine, it should measure close to 14.7 volts. The battery symbol light comes on when the alternator is not charging the battery. Engine running, measure the voltage across the battery and the alternator output, it should be the same. If the alternator is 14.7 and the battery is below 13 volts, then you have a blown fusible link in the alternator output wire.
Thread Starter
Pro
Joined: Sep 2006
Posts: 702
Likes: 2
From: Conyers Ga
Ok, heres what I have. The car has sat idle since Sunday. The battery voltage with the car off today was 12.9. The alternator was the same. I started the car and maintained the same voltages at both the battery and alternator but the dash read 11.8. After a minute or so the battery light came on. I let the car idle and the dash reading eventually went up to 14.2 but the battery and alt stayed at around 12.9.
The car started fine and the voltage was the same at the battery since monday so I know there's no drain on the system.
The car started fine and the voltage was the same at the battery since monday so I know there's no drain on the system.
Safety Car
Joined: Jul 2004
Posts: 3,834
Likes: 30
Originally Posted by nyernga1
Ok, heres what I have. The car has sat idle since Sunday. The battery voltage with the car off today was 12.9. The alternator was the same. I started the car and maintained the same voltages at both the battery and alternator but the dash read 11.8. After a minute or so the battery light came on. I let the car idle and the dash reading eventually went up to 14.2 but the battery and alt stayed at around 12.9.
The car started fine and the voltage was the same at the battery since monday so I know there's no drain on the system.
The car started fine and the voltage was the same at the battery since monday so I know there's no drain on the system.
EDITED..i think your alternator is history....
Last edited by Da Mail Man; Oct 19, 2006 at 07:37 PM.
Safety Car
Joined: Jul 2004
Posts: 3,834
Likes: 30
Originally Posted by nyernga1
Well since it's only a month old, I'm sure I'll have no problem returning it.
.....i had one like that many years ago which took 10-20 seconds to product "decent" voltage......took it back under warranty and all was well....
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