You want it to carry the correct current. A cable of 1000 strands will carry half again the amount of current a cable of 100 strands. Both being the same gauge.

 

If your HHR is a 2008 disconnecting the battery will kill the TPMS, unless you already got the firmware update.
Frequent parasites are OnStar and EVAP testing and sound equipment. Check the I/M readiness, if EVAP is "not ready" it runs testing when the engine is turned off until it passes. Every time you disconnect the battery the testing has to start over from a blank slate, EVAP can take about 10 days to finish.

 

And I see Lee is in NY. If emission testing is coming up, he better get this figured out quick. Or is it just NYC that tests?

 

Thanks for the info. Mine is a 2006 so I don't have the 2008 issues. I no longer subscribe to OnStar could it still be draining? How to check I/M?

Thanks again

 

Pull the battery cable and connect a small light bulb between the cable and the battery. pull fuses till the bulb goes out and you'll have found the culprit.

 

Any code scanner can check I/M readiness.
OnStar might try "calling home" even with no subscription, pull fuse #56 under hood, unless you use XM/Sirius (same fuse).