Hi guys. been a while since my last post.
I'm just wondering if anyone has ever measured the normal parasitic battery drain on a Cavalier.
I'm getting 60ma which I think is a bit high. Battery is dead after 10 days, maybe less when it's colder outside.
60ma is 1.44amps a day so 10 amps a week. I've just bought a new battery but don't want to fit it without looking at this drain. The battery on it now is about 2 years old and I'm sure the constant running down has ruined it.
I've pulled all fuses from both fuse boxes, disconnected the alternator, disconnected various relays, disconnected the immobiliser, disconnected the central locking relay and even removed the stereo and interior light fitting but still get the constant 60ma drain. Everything seems to be working normally, I've checked to make sure the elecric windows are shutting down after the drivers door has been opened and closed. Alternator was replaced last year and is charging correctly. Is there a fuse for the alarm system even though I'm not activating it via deadlocking. Also are there any fuses I'm missing? Are there any above the fusebox in the dash? I can see a couple of relays inside the dash above the fusebox, either purple or pink but not sure what they are for
Parasitic battery drain
Moderator: Robsey
Re: Parasitic battery drain
When I've had fast drains on batteries I have found failed diodes in the alternator has been responsible more than once.
Re: Parasitic battery drain
There are only two main fuse boxes.
One under the dash that all Cavaliers have.
Cavaliers with V6 engine, factory immobiliser / alarm or air conditioning, have another fuse box at the back of the engine bay.
Are there any retro-fitted extras?
I recall many incidences of the boot light switch or it wiring being faulty causing a drain even though the boot / hatch is closed.
If you suspect the alarm, then you can unplug it from it's yellow connector located in the side wall next to the glove box.
If the yellow lights on the window switches are illuminated, then the windows are 'live'. If the lights are off, then the windows should be 'dead'.
The "expected" drain should be :-
1 - the clock / dual info display / fuel computer,
2 - Vehicle alarm sensors (ultrasonics) and status LED.
One under the dash that all Cavaliers have.
Cavaliers with V6 engine, factory immobiliser / alarm or air conditioning, have another fuse box at the back of the engine bay.
Are there any retro-fitted extras?
I recall many incidences of the boot light switch or it wiring being faulty causing a drain even though the boot / hatch is closed.
If you suspect the alarm, then you can unplug it from it's yellow connector located in the side wall next to the glove box.
If the yellow lights on the window switches are illuminated, then the windows are 'live'. If the lights are off, then the windows should be 'dead'.
The "expected" drain should be :-
1 - the clock / dual info display / fuel computer,
2 - Vehicle alarm sensors (ultrasonics) and status LED.
Re: Parasitic battery drain
No extras fitted. It's the 1.7td cdx.
I have a digital voltmeter which comes on with the ignition. I have it because the alternators on these tend to overcharge when failing, so I can tell if it will start or not in the morning. It will actually start at 11.9v showing as long as the temps are not below freezing and it starts as soon as I turn the key lol
As you say I'm expecting drain from the memory function on the stereo, the immobiliser and the clock/temp display. I've had the window switches staying illuminated in the past, foam insulation behind the drivers pin switch caused that.
I'm still getting the 60ma drain with all the above disconnected. I even disconnected the flashing immobiliser LED.
I will try unplugging the alarm. The alarm still works as it should for a 25 year old car which surprised me when it went off while I was messing about under the bonnet.
What really narks me is dad has a 18 year old Toyota and he's been using it maybe once every two to three weeks since last March lockdown and he has no problems at all with flat batteries!
I've bought a 77Ah Varta with 780CCA as a replacement. It's a 096 but just fits in the tray.
Thanks for the replies
I have a digital voltmeter which comes on with the ignition. I have it because the alternators on these tend to overcharge when failing, so I can tell if it will start or not in the morning. It will actually start at 11.9v showing as long as the temps are not below freezing and it starts as soon as I turn the key lol
As you say I'm expecting drain from the memory function on the stereo, the immobiliser and the clock/temp display. I've had the window switches staying illuminated in the past, foam insulation behind the drivers pin switch caused that.
I'm still getting the 60ma drain with all the above disconnected. I even disconnected the flashing immobiliser LED.
I will try unplugging the alarm. The alarm still works as it should for a 25 year old car which surprised me when it went off while I was messing about under the bonnet.
What really narks me is dad has a 18 year old Toyota and he's been using it maybe once every two to three weeks since last March lockdown and he has no problems at all with flat batteries!
I've bought a 77Ah Varta with 780CCA as a replacement. It's a 096 but just fits in the tray.
Thanks for the replies
Re: Parasitic battery drain
Did a bit more digging today, bloody freezing out. The large connector behind the passenger kick panel was soaking wet, looks like its been that way for a while. I think the seam sealer in the scuttle has cracked letting water in. Dried it all out and cleaned all the contacts. What a bloody fiddly place for it.
Checked the drain after that and it's fluctuating between 30/40ma
pulled the radio fuse and it dropped to 20/30ma.
Took a chance operating the central locking with the meter connected and of course it rose to 10amp but dropped back to 30/40ma even with the alarm activated. It was too cold for any further messing about. I think 30/40ma is acceptable though I'd prefer 20/30ma.
I've put the old battery on charge to see what voltage it charges up to and if it goes up to 12.6 I'll see if it stays at that while sitting.
The 096 Varta fitted a treat so I'll see how it goes
Checked the drain after that and it's fluctuating between 30/40ma
pulled the radio fuse and it dropped to 20/30ma.
Took a chance operating the central locking with the meter connected and of course it rose to 10amp but dropped back to 30/40ma even with the alarm activated. It was too cold for any further messing about. I think 30/40ma is acceptable though I'd prefer 20/30ma.
I've put the old battery on charge to see what voltage it charges up to and if it goes up to 12.6 I'll see if it stays at that while sitting.
The 096 Varta fitted a treat so I'll see how it goes