My Jeep Compass Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
I have a 2008 Jeep Compass. This past week it has not started on it's own. I got it boosted twice now, and once started it runs fine. Although it goes dead again the next morning.
The engine malfunction light as well as the ETC warning light now stay on once I try to start the vehicle and it won't start.
Is this an easy fix such as replacing the battery, or does it sound more complicated?
 

·
Super Moderator
Joined
·
534 Posts
I would try swapping in a battery, as that sounds like what the issue could be, do you have access to a battery you could try before buying one?
 

·
Registered
Joined
·
56 Posts
Yep, it might be a bad battery or alternator.

To test, check the voltage on the battery with a multimeter while the engine is on. It should read around 14.7 volts, which would mean good alternator but bad battery in your case. If it's around 11 or 12 volts, then the alternator is bad.
 

·
Registered
Joined
·
1,897 Posts
Yep, it might be a bad battery or alternator.

To test, check the voltage on the battery with a multimeter while the engine is on. It should read around 14.7 volts, which would mean good alternator but bad battery in your case. If it's around 11 or 12 volts, then the alternator is bad.
Do this first as you're throwing parts at it although at the 4th year and more your battery is on borrowed time. Meter it as indicated. When off it should be around 13VDC running depending on the charge level 14V or higher but at 14.7VDC it could start over charging and gassing. Usually 14.5V is optimal especially when cold weather hits you need almost a .5VDC more and why some vehicles charge higher in the cold than summer.

You could have something draining the battery. If you do replace the battery you still should check the voltage you get when its running to verify your alternator is working as it should. Note: New batteries are not fully charged and it takes hours of driving to top them off.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #5
still having problems

Battery was replaced to a brand spanking new one..something is still draining it. The engine light comes on as well. How would I know if this is an electrical problem or the alternator? I'm not in the best know how for cars.
Also, if car is started, is there any possibility of it slowing down and stopping while I am driving from point A to point B? Sorry for asking so many questions, but the garages are very busy right now and it might be a bit before I can get it in.
 

·
Registered
Joined
·
1,897 Posts
See my post #4, have you checked it with it running. If the voltage is not around 14vdc running and below 13.5vdc then the vehicle will stop when its below 11vdc due to lack of power in the battery (dead). Normally an idiot light would be on for an alternator problem but again its an idiot light not a voltmeter.

Something is on accidentally or faulty draining it when sitting. Only you or a mechanic can look over the vehicle for that problem.
 

·
Registered
Joined
·
80 Posts
There will always be some battery drain when stopped and locked up as electronics is always on - alarm, remote door controller etc.

Too much drain will flatten the battery, but it would have to be a significant current draw.

Isolation(pull fuses) is a quick way to track down the source of drain.

Take her to an Auto Eclectrican
 
1 - 9 of 9 Posts
Top