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

5563 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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Yes. The issue is one of the codes cannot be cleared by any mean. And because it cannot be cleared the car cannot be plugin charged. The entire body management module has to be erased and reprogrammed from scratch and only a dealer has the equipment to do that.

So that is fine so long as it is still under warranty but once the Voltec warranty expires expect a $100+ bill from a dealer to reflash the module.
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