E7A Checking the Mass Air Flow Sensor
E7A Checking the mass air flow sensorTools:
- Multimeter
Start the engine and let it run at idling speed. Check the CO content. If it is higher than 6 % it cannot be adjusted by means of the CC adjusting screw. Switch off the engine.
1 Remove the mass air flow sensor from the air cleaner side. Check whether the hot wire (filament) is intact.
Hot wire (filament) defective:
Change the mass air flow sensor.
Hot wire (filament) OK:
Check the mass air flow sensor connector and wiring by:
- Unplugging the mass air flow sensor and control module connectors and removing the cover from the control module connector.
- Check that the wiring and connections are OK.
- If the wiring is OK, plug in the control module connector.
2 Check the hot wire (filament) burn-off function. (See "Checking the hot wire (filament) burn-off function", section E7B.)
Mass air flow sensor connector
Pin No. Component
1 Control module connector pin 8 (red/white; RD/VT)
2 Main relay pin 87b (brown/white; BR/VT)
3 Control module connector pin 6 (blue/white; BL/VT)
4 Engine grounding point 552 (black; SV)
5 Control module connector pin 7 (orange; OR)
6 Control module connector pin 14 (white; VT)