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So, I got the dreaded "Service High Voltage Charging System".

5564 Views 10 Replies 7 Participants Last post by  indyflick
....but I'm not that worried about it as I know (having learned about it here) that it's almost certainly just the typical coolant tank sensor issue. I checked the battery coolant level and it's right where it's supposed to be with zero sign of any leakage anywhere. FWIW as well the car has had all the updates done, anti-tamper guard on the coolant tank, etc.

The car is still under the Voltec warranty so I have an appointment to take it to the dealer Wednesday.

Two questions - I hooked up my scantool and here's the codes I got:

Are these typical of the codes one would expect for the sensor issue?

And secondly, I had always been under the impression that the SHVCS code/error was only clearable by a dealer (?), but since it was stopping us from charging I commanded my scantool to clear the codes and boom, check engine light went off and the car honked, dash light turned green, and it started charging immediately. It tossed the code again the next day (Saturday) but again I reset it (with the same success) and it's been fine since, hence why I'm sure this is just an intermittent sensor thing.

Is this actually normal for those of us with our own scantools to be able to reset this, and all the stories about "requiring an expensive visit to the dealer to have it reset" is just specific to those without their own scantool?
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I guess, in short, what I'm getting at is this - do I even need to bother going to the dealer Wednesday, potentially fighting with them about getting this covered under warranty, only to end up not much further ahead other then to maybe get a new battery coolant bottle with the same inherent issue?
IMO if you want peace of mind get it re-flashed and fixed then add the WOT replacement. BTW it is not a bottle but a sensor that attaches to the bottom of the bottle.
A new bottle is included in the update for the 2011 and 2012 models, as well as the sensor. The original bottles wouldn't have had the molded on holder for the sensor that was added and spliced to the wiring. If the OP is lucky, the dealer will perform the update for splicing in the wiring for the sensor, will add the new bottle and will reprogram HPCM2 all under warranty, as all this was covered in GM issued recall #11188.
Thanks for the clarification.
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