I thought I'd post some pictures to show you what's coming your way in the near future. This is a 2013 Malibu with E-Assist technology. The vehicle came in with a low battery message on the DIC. Checking the 12 volt battery, KOER, 12.4 volts was the maximum reading. Scanning the control module systems, the HPCM set P0AC4-00 and P0CA2-00. The TCM set P0562-00.

The P0562-00 is a low voltage code, the P0AC4-00 is a requested illumination code. The code concerning the failure is the P0CA2-00. This is a 14v. Power Module Step Down Voltage Performance code. The SGCM contains the HPCM, 14 Volt Power Module and the Drive Motor Control Module. It is serviced as an assembly. The 14 Volt Step Down Power Module uses switched MOSFET transistors to convert the 130 Volts from the Hybrid battery to 14 volts to supply the 12 volt system. When the power module sees a MOSFET failure, it will disable the 12 volt system feed and set P0CA2-00.

The Battery module must be removed from the vehicle to replace the SGCM. Here is a picture of the battery module in the vehicle with the high voltage interlock cover removed. If you look carefully, you can see a tie wrap holding the high voltage interlock switch in the off position for my safety.

[Drive Motor Battery Module]

Next, the internal components are visible with the cover removed. Caution is necessary as the module is always "hot" under the cover.

[Battery Module With Cover Removed]

Next, the new SGCM is installed on the left side of the module and is ready to re-assemble.

[SGCM Replaced]

Not that difficult a job to do. Just be careful so you don't end up a crispy critter.

James from Florida

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