[amidgeha]

Sensor Reference Voltage (B) Circuit/Open

The control module has 2 internal 5-volt reference buses called  5-volt reference 1  and 5-volt reference 2 . Each reference bus provided 5-volt reference circuit for more than one sensor. Therefore, a fault condition on one 5-volt reference circuit will affect the other 5-volt reference circuits connected to the reference bus. The control module monitors the voltage on the 5-volt reference buses.

Cause:
Faulty Engine Control Module (ECM)
ECM harness is open or shorted
ECM circuit poor electrical connection
Shorted sensor on 5 volt circuit

Symptoms:
Check engine light