P0040 Cadillac 1/1 And 2/1 O2 Sensor Harness Connectors Reversed
Possible causes
– 1/1 And 2/1 O2 sensors harness is open or shorted
– 1/1 And 2/1 O2 sensors circuit connectors (wrong connection)
– Faulty Powertrain Control Module (PCM)
– 1/1 And 2/1 O2 sensors circuit connectors (wrong connection)
– Faulty Powertrain Control Module (PCM)
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0040 Cadillac Description
At ignition on the Powertrain Control Module (PCM) checks the voltage on the ground side of the O2 sensor harness connector. If voltage is higher than two volts the P0040 Cadillac code will set.
Cadillac Vehicle:Cadillac CTS Coupe, Cadillac CTS-V Coupe , Cadillac Eldorado , Cadillac Escalade EXT , Cadillac ATS , Cadillac CTS , Cadillac CTS Sedan , Cadillac CTS Sport Sedan , Cadillac CTS-V , Cadillac CTS-V Sedan , Cadillac Catera , Cadillac DTS , Cadillac DeVille , Cadillac STS-V , Cadillac STS , Cadillac Seville , Cadillac XTS , Cadillac XLR , Cadillac XLR Platinum , Cadillac Escalade , Cadillac SRX