P0643 VOLKSWAGEN Sensor Reference Voltage A Circuit High

Possible causes
– Faulty Engine Control Module (ECM)
– ECM harness is open or shorted
– ECM circuit poor electrical connection
– Shorted sensor on 5 volt circuit
When is the code detected?
The Engine Control Module (ECM) has detected the sensor 5 volt reference circuit voltage is higher than expected
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)