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electrical problem..... need help!

951 views 8 replies 6 participants last post by  Jayare 
#1 ·
i have a 1988 300e i have been having big problems starting my car, a just replaced the battery 1 week ago and now my car won't start.

i just noticed the other day that the check egine light was on, i dont know if that is related to the battery problem or something else... would it be possible for the "check engine light" to drain the battery, or would it be something else like an alternator. i'm really getting sick of this car! please help
 
#5 ·
Battery

If you jump it it starts? First jump it, a bad cell in a battery will cause all the problems you talk about except for the check engine light. Normally replacing the battery turns the light out. I would take that battery back and try again, if that doesn't work replace the OVP another culprit.
 
#6 ·
What made you replace the battery in the first place? Was it the same problem before? Have you had any other work done on the car in the past month or so that may have had an impact [intentional or not]?
 
#7 ·
i replaced the battery because i live in ohio and we had about a week of sub zero temperatures and my car wouldn't start, so the guy who replaced it said that the battery was pretty much frozen.

after i got it fixed i drove it for about a week then the car sat for 2 days.... i went to drive it and it was dead. so i took it home because my dad has a electric powered car battery chargers, and i charged it for like 4 hours and nothing happened. so thats whats making me think the alternator is dead, i mean the battery won't hold a charge.
 
#8 ·
Battery

If the battery won't hold a charge its the battery, get a new one (take that one back exchange it) . If your alternator is bad replace the regulator and you should be fine, but check the output voltage while its running first if its between 13-14.6 you should be fine.
 
#9 ·
If the battery won't hold a charge, I'd have it checked out at some place other than where you purchased it. Even if the alternator is dead, the battery should still hold a charge. The alternator's on our cars seldom go dead. However, the voltage regulator's do. They are simple an inexpensive to replace. I bought mine at NAPA for less than $40.00. The regulator is located on the back of the alternator and is held in place by two phillips head screws. Simple to DIY if you can get under the car.

You say that the car will run when it is jump started. If so, use a volt meter to measure voltage at the battery terminals while the car is running. If the alternator/regulator are doing their job, you should be seeing a reading of 13+ volts. Without the engine running, you should see some reading slightly less than 13 volts with a fully charged battery.

Good Luck,

Jayare
 
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