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

5567 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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Following up....SHVCS hasn't popped up again since, so it was clearly a very intermittent problem.

Most interestingly, the P1FFD code is also gone - I scanned it last night and everything is showing completely normal again now.

I still don't understand what all the hubub about "needing" a dealer visit (and reprogramming modules etc) to resolve SHVCS is all about - it seems based on my experience that anyone with a code reader can clear the issue, activate charging again, and even the remaining P1FFD "permanent" code cleared after enough driving cycles.

I'm not going to rush for the WOT bypass at this point unless the issue turns out to be semi-regular - a once every 3 months thing I can simply clear and be done with it.
It would be interesting to know if all of the codes in your case would have eventually cleared without a scanner at all. I realize this would likely require running the engine once the battery was depleted because you couldn't charge.

You may have a unique circumstance that resulted in the same general "false positive" many others are experiencing. While your situation is indeed interesting, at this point I'm still more comfortable in having bypassed the sensor all together.
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