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Service High Voltage Charging System - Out of warranty

17838 Views 31 Replies 17 Participants Last post by  Cord
Got in my 2013 volt this morning to go to work, go the "service high voltage charging system" error code. What exactly does it mean? New charger needed?

Battery coolant level is fine.

I'm at 145k miles so I'm guessing out of warranty or would this be included on the 150k voltec warranty?

I have only had the car for a couple months :(
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I just remembered I carry a bluetooth OBDII in my car, Fault Codes are

codes are


edit: I was able to reset them with torque and my bluetooth tool despite being told it's not possible.
So I just order that sensor bypass and the problem should be solved?
Thanks, I wonder if it's just a software bug or my battery is going bad. I guess if it's an issue with the battery It would come back soon.
So I bought the sensor bypass and I was good for a day after installing it, but today it just threw the same 3 codes.

Does that mean it's the battery that went bad then?

I'm going to schedule a visit to the dealer, so i guess i should plug back in the battery coolant level sensor? Unhook the ground and all that again?
If it is related to the coolant sensor going bad, the codes appear to be cleared but they will return. There is a module that has to be reprogrammed/reflashed to clear them permanently. FYI, I have had the defeat plug installed and have had the car in and I don’t believe anyone has even noticed or clued in. I lost the original sensor too so I don’t have one to put back in even if I wanted to. Explain to the dealer you are aware of the sensor issue and that you have done what many others have done to avert a costly and unnecessary repeating repair due to the high failure rate of the sensor. Show them the 520 or so comments on this forum about it and that WOT who created the fix is a GM mechanic certified on the Volt.
The codes appear to be cleared but they return once they are there? That seems odd, I thought I read they can't be cleared? I guess I'll go uninstall the sensor then and hand GM a few hundred bucks to clear the codes.

I'm planning to sell the car next month. So should I have them go ahead and replace the sensor, then bypass it when I get it home?

Bulletin No.: PI0961A
Date: November, 2013

"Scan modules HPCM2 has codes. P1FFF and P0AA6 current.

Scan check data. Isolation resistance is ok, at 325k ohms.

Perform update on BECM and HPCM2 as per bulletin PIC5920.

Also replace Coolant level sensor for high voltage battery pack with updated unit for P1FFF.

Bulletin PI0961."
Thanks, what should I expect this to cost me? I reconnected the sensor and it's ready to go into the shop.
So it turns out they just updated software for two modules and charged me $232. They were going to charge me an additional $145 for diagnosis. Tech said they don't typically add the diagnostic fee into the repair bill :( Kind of lame since that was just to identify the error codes, but they waved the additional $145 this time, so that's nice. (most dealerships roll the diagnostic into the work if you decide to have it done?)

They Performed Calibration updates on the HPMC2 WCC:CBCC0 and BECM WCC:CD1C0

This was in accordance with Bulletin PIC5920G

Posted 2017-08-15
060000 ENGINE (PWS) bulletin for the 2013 VOLT
This Preliminary Information communication provides information to the technician about vehicles that will not charge and Service Engine Soon Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Codes P0AA6 and/ or a P1F0E

NHTSA has assigned ID #10114062 to this bulletin. You can get more detailed information on how to fix the problem.

They did not replace the coolant sensor.

I wonder if I should even bother re-installing the sensor bypass?

I'm wondering how often I will need to take the car in for updates and re-calibration?
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