P0040 Audi 1/1 And 2/1 O2 Sensor Harness Connectors Reversed

P0040 Audi 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)
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0040 Audi 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 Audi code will set.

Audi Vehicle:Audi A1,Audi A3,Audi A1,Audi A3,Audi A1,Audi A3,Audi A4,Audi A5,Audi Q3,Audi A5,Audi Q5,Audi A3,Audi A4,Audi A5,Audi TT,Audi Q3,Audi Q5,Audi S3,Audi TTS,Audi RS 3,Audi TT RS,Audi A7,Audi Q7,Audi A8,Audi A6,Audi S4,Audi S5,Audi Q5,Audi S6,Audi S8,Audi S5,Audi A8,Audi R8 V8,Audi RS 5,Audi S6,Audi R8 V10,Audi R8 GT,Audi A8L