Coololdcars

My HHR is suffering a battery draining issue, it went dead sometime over a weekend, now overnight???

Doc brown

How old is the battery? If you get a full charge on the battery does it hold an over night charge if you disconnect it after the full charge?

RJ_RS_SS_350

Fully charge the battery, then go directly to the nearest auto parts store for a free battery load test and charging system test.

Coololdcars

I load tested after the last charge. It tested ok. Usually takes a weekend to go dead, but went dead overnight this time

whopper

Unless you are well versed at diagnosing electrical issues, and have the appropriate diagnostic tools such as a VOM, you need to take it to a repair shop that can track down the cause of the parasitic drain. Do you have any electrical tools such as a multimeter, and have you worked on electrical systems before?

RJ_RS_SS_350

Cool, not many people have their own load test equipment.

Cat Man HHR

Old school quick check.
Remove the negative battery cable, hook a test light between it and the negative post of the battery.
If it lights you got something in the car that's draining the battery.
Make sure no lights are on or anything else when this is done.
For it to go dead in two days the car has a heavy draw from something.
How many volts is the battery when dead ?
How many volts is it when fully charged ?

whopper

x2 - however, however like Cat Man says, make sure all the lights have to be off (including the interior lights), key out, nothing charging in the dash power outlets, and be prepared for an initial current draw that will drop down after a few minutes (that is normal). In the end, the current draw should be in the neighbourhood of ~25-75ma i believe.

Problems others have encountered with these symptoms:
- after market radio/stereo/subwoofer installed incorrectly
- cell phone/GPS etc. left charging
- defective alternator

Oldblue

And let’s not forget loose and or corroded ground terminals . Like the front of the transmission, just down to the right of the oil filter cap.
#2 in this



Then the rad cradle ground,#2 in this




any frayed wires under the EVAP purge valve

RJ_RS_SS_350

After you remove the key and shut the door, wait at least 10 minutes for the RAP before your test.

So you have to shut the hatch, and access to the battery will be challenging.