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CTS-V Electrical Trouble

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Old Jun 15, 2011 | 08:04 PM
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Default CTS-V Electrical Trouble

My friend has problems with his caddy. It suddenly threw P0641 and P0651 codes and went into REP mode. Searching for the solution online just tells me it could be anything. I hooked up my HPT scanner to reset the codes but it throws them immediately. Any suggestions?

I can only find instances of P0641 OR P0651 by searching. I thought maybe the fact that they've both been thrown on his car might be a clue as to what the problem is. Please help.
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Old Jun 16, 2011 | 07:00 AM
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5 vdc reference voltage is a sensor volt problem. It could be tied into the pcm having failed. That's the reason for the limp mode.

I'd start with an inspection of the PCM plugs/pins, and the associated wiring, sensor connections....

A datalog may show sensor problems, etc.
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Old Jun 16, 2011 | 03:15 PM
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What year is it?
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Old Jun 19, 2011 | 12:54 PM
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I've been out of town, but I'm back now. It's an '06. I'll see if there's been any progress on the car this evening and take a look at the wiring. I'll also set up a config file to look at all the sensors I can think of and see if any of them are acting strange.
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