P1639 Acura PCM 5 Volt Reference Voltage Circuit Condition
Possible causes
– Sensor using 5 volt reference line shorted to ground
– Circuit short to ground
– Circuit short to ground
What about the obd code?
If the voltage is out of tolerance, the PCM will set DTC P1639 Acura.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1639 Acura Description
The powertrain control module (PCM) uses the 5-volt reference 2 circuit as a sensor feed for the A/C refrigerant pressure sensor. The PCM monitors the voltage on the 5-volt reference 2 circuit.
Acura Vehicle:
Acura ILX, Acura MDX, Acura RDX, Acura RLX, Acura TL, Acura TSX, Acura ZDX, Acura CSX, Acura EL, Acura Integra, Acura RSX, Acura Legend, Acura Vigor, Acura CL, Acura SLX, Acura NSX, Acura RL, Acura ZDX