Cause
Shorted sensor dragging the reference down
One failed sensor pulling the shared five-volt reference down for every other sensor on it. So a spread of unrelated sensor codes can be caused by exactly one faulty sensor — and unplugging them one at a time until the reference recovers is what finds it, which is faster than testing each in turn.
Typically a moderate job.
Codes this can cause (9)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0641 Sensor Reference Voltage A Circuit Open Likely for this code High
- P0642 Sensor Reference Voltage A Circuit Low Likely for this code High
- P0651 Sensor Reference Voltage B Circuit Open Likely for this code High
- P0652 Sensor Reference Voltage B Circuit Low Likely for this code High
- P0697 Sensor Reference Voltage C Circuit Open Likely for this code High
- P0698 Sensor Reference Voltage C Circuit Low Likely for this code High
- P06A3 Sensor Reference Voltage D Circuit/Open Likely for this code High
- P06D3 Sensor Reference Voltage E Circuit Low Likely for this code High
- P24D0 Particulate Matter Sensor Supply Voltage Circuit Low Moderate
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