Trouble Ticket Help Requests for DTC P1639
|2002 Chevrolet Impala LS 3.8L MIL Lamp on VIN: 2G1WH55K12
P1639: 5-Volt Reference 'B' Circuit Malfunction. ... checked for the 5v on each of the sensors,fuel tank pressure sensor,A/C high side pressure sensor,EGR valve ,TPS,and MAP sensor all good.If I disconnect one at a time and start car both the p1635 p1639 codes set immediatly...
|July 01, 2013|