Had this vehicle in, failed MOT on emissions. Fail on Lambda 1.42 1St fast Idle 1.28 on the 2nd.
Mil Lamp on with codes logged P0103 MAF High input. P0112 Intake air temp. P0132 02 Sensor Circuit Bank 1 Sensor 1. Investigation shows power on the earth wire to 02 sensor. This ground is common to the MAF intake air & 02 sensor. Have had difficulty getting pin data for this vehicle. I've got a five wire MAF. Readings as follows. Pin 1 (or perhaps pin five) Blue 11.8v, Pin 2 Red 12.25v, Pin 3 Orange 12.95(should be ground I think) 12.95v, Pin 4 Grey 14.4v, Pin 5 Yellow 7.2. All at idle. The orange I assume should be ground. If we introduce an earth to it we get the correct intake air temp, but the car runs very lumpy with an erratic 02 sensor trace. The orange wire seems to route back to pin 36 on the ECU. getting continuity between this, the MAF & 02.

Does anybody have any correct pin data for this vehicle or have any ideas?