Code 1121: MAF Sensor
- Voltage Supply: Connect DVOM between ground and terminal No. 3 of MAF sensor wiring harness connector. See Fig 1
. Turn ignition on to check voltage supply to sensor. If reading is 4.7-5.3 volts, go to next step. If voltage is not 4.7-5.3 volts, check Blue/Green wire back to DME control unit.
- Voltage Drop: Disconnect air filter hose. Using jumper wires, connect terminal No. 3 of MAF sensor wiring harness connector to terminal No. 3 of sensor, and connect terminal No. 4 of wiring harness connector to terminal No. 4 of sensor.
- Connect DVOM between ground and MAF sensor terminal No. 2. Turn ignition on to check voltage drop across sensor. With MAF sensor plate closed, reading should be 250-260 millivolts.
- Using screwdriver handle, press MAF sensor plate to full throttle position. Reading should gradually increase to about 4.6 volts. If voltage values are incorrect, replace MAF sensor.
Courtesy of PORSCHE OF NORTH AMERICA, INC.