Typical lifetime of 12V battery...

If this is a habit, then try replacing the offending lights with LED versions. While it won't cure the problem, it will reduce the current drain by about 90%, giving you much more time to intercept the problem before the battery goes dead.

 

Is there a way to identify this with a Scan Gauge II? If so, can someone please describe it?

 

I have seen battery protectors that automatically disconnect the battery if the voltage falls to 11.7V and such. Any one with experience with one of these?

 

You can read the 12V battery with SGII, but it would be difficult to determine exactly what was going on without knowing what the normal readings were first. A typical voltage reading is going to be >14V when the car is first made ready, then after 5-10 minutes it should start to fall to 13.6-13.8 volts and stay close to that. If the voltage never goes below 14V, or never gets above ~13.2V, there is some problem with the battery. If the Converter (the 12V charger part of the inverter) temp reading goes up well above normal, then you know that the battery is getting more current than normal. That could also happen with a good battery that has been discharged.

It's one of those "it depends" situations that just needs to looked at now and then to get a base line for your car.

 

Thanks for the explanation. I do see this behavior, it does fall to 13.5 volts after a few minutes of driving. One thing I have noticed though is that, once I arrive in the garage and hit the "P" parking button, the voltage goes up to 14.4 volts until I switch the system off. Is this normal?

Any way to measure the Inverter/Converter temperature with the SGII or any other such device? Or otherwise see the current being supplied via the SGII or such? TIA.

 

Battery still alive. I Have a 2009 with 91,000 miles bought in Dec 2008, so 7 years 5 months. I live in northern Indiana.

 

I just replaced my 2004 battery that was 12 years old with 165000 miles on it. I went to a local interstate battery store and got an AGM refurbished battery for 75 installed. Pretty good deal in my mind.

 

That's interesting. How would that work? They reuse the case, and maybe the posts, new innards?