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Intermittent parasitic draw on '04

09-05-2014, 07:33 PM
I have a VERY intermittent parasitic draw on my '04 Cavalier. It will go weeks or months with no ( <0.005A ) draw, then the battery will go dead or very low in under 8 hours. It has happened about 5 times over the last year. I don't drive the car much and it had only happened when the car sat for a few weeks until last week when I parked it at work and it wouldn't quite start after sitting for 8 hours (engine turned once or twice before the starter started clicking). I connected a jump pack and checked the draw after 10 minutes, it was at 0.001A.

Battery load tests good and alternator charges good.

Anyone run into this before? I haven't been able to catch it while it's happening to be able to test anything. Electrically, it's all stock, except a relay which is controlled by the fuel pump power circuit (on with fuel pump on). I swapped the relay with another car to test and it didn't change.


Blue Bowtie
09-06-2014, 11:04 AM
Up to about 35mA (0.035A) is fairly normal for parasitic draw for the on-board electronics. Since the problem seems to be so intermittent, it may take some time to isolate the cause. My initial suspects would be the RAP function and any delayed interior lighting. If there is a trunk or glove box light, verify that the switches controlling them are not on the borderline of making/breaking when the lid is closed. You may want to verify the brake light switch is also not on the verge of closing with no pedal travel.

Aside from those, you almost need to catch it at a time when load is higher to diagnose it fully.

BTW - Is the radio/head unit stock or aftermarket?

09-24-2014, 04:26 PM
I removed all the interior lights to see if that would keep the battery from dying... it didn't.

The radio is the factory unit... From what I've seen, the radios drawing power make the battery die after several days or weeks and I've never seen one intermittent (I'm not saying that's not it though). I was leaning toward that being it until the battery died while I was at work. I do have an aftermarket radio I could throw in, I just need the adapter for the car.

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