GM Volt Forum banner
1 - 2 of 2 Posts

·
Registered
Joined
·
605 Posts
Is it possible that the 12v battery is just unable to deliver the amperage needed? Sometimes the volts check out OK but they can't deliver the amperage when needed. I just checked the voltage on my 12v battery in the trunk of my 2017 and got 13.35v.

Edit: the car was plugged into the 120v charger at the time (charging had completed) so that 13.35v may be high due to being plugged in.

Mike
 

·
Registered
Joined
·
605 Posts
If I was in your situation, I think I'd see if I could find another vehicle with a compatible 12v battery that I could borrow just to test that. Then maybe check all the ground wires you can find. Faults in multiple computer systems can sometimes be a bad ground.

Edit: I was able to find this:

Date Reported
SEPTEMBER 01, 2013
NHTSA Reference
#10053870
TSB Reference
#SB-13202
Description: CHEVROLET: ON SOME VEHICLES, WATER MAY TRAVEL ALONG DRIVER MOTOR 2 POSITION SENSOR WIRE SET A DIAGNOSTIC CODE, IN WET WEATHER, AND CAUSE CHECK ENGINE LAMP TO ILLUMINATE AND WOULD NEED TO REPROGRAM POWER INVERTER MODULE. MODEL 2011-2013 VO

Edit 2 (did some more reading, sorry):

Based on this and other info: http://www.autocats.ws/manual/chevrolet/tis0911/en/documents_2012/Volt/SM-R/92422548.en.html

It looks like the motor position sensor is either sending a garbled signal or the motor control module is faulty and isn't picking up the signal properly. The sensor is likely producing something akin to a square or sine wave and the motor control module probably examines the signal to determine motor speed and/or position. Looks like the signal is read as "garbage" by the motor control module either due to a bad sensor or a bad module (or even a bad wiring or water intrusion problem) and that throws P0A45. Due to the P0A45, the system throws P0AC4 to turn on the MIL.

Probably still worth checking the battery and grounds first though, as that's likely the easiest.

Mike
 
1 - 2 of 2 Posts
Top