Operation CHARM: Car repair manuals for everyone.

Component Tests and General Diagnostics

Air Flow Meter/Idle Valve/Throttle Switch Location:





1. Disconnect the harness connector from the air flow meter.

Injection Electronics. Wiring Diagram:





2. With the ignition switch in the run (ON) position measure the following voltages at the harness connector.

^ Gray/white wire (terminal 3) and ground = Approx. 5 volts
^ Gray/white and gray/yellow wire (terminals 3 and 2) = Approx. 5 volts
^ Gray/white and gray/blue wire (terminals 3 and 4) = Approx. 5 volts

3. If any voltage is incorrect, check and repair associated connections and wires for opens and shorts to voltage and ground.

^ If wires and connections are OK, replace the DME control unit.

4. If all voltages are correct check for continuity between the following terminals at the air flow meter connector (male plug). Measure between pins:

^ 2 and 4 = Continuity
^ 2 and 3 = Continuity


^ If any results are incorrect, replace the air flow meter.
^ If all results are correct, proceed to step 5.

5. Reconnect the air flow meter connector and remove cover from rear of connector.
6. Measure the voltage between gray/yellow wire (terminal 2) and ground while moving the intake air flap manually.

^ If voltage varies between approximately 0.5 and 4.5 volts, check or repair wire to terminal 7 of the DME harness connector for an open circuit. If wire is OK, replace the DME control unit.
^ If the voltage does not vary between 0.5 and 4.5 volts, check or repair wire to terminal 7 of the DME harness connector for short to ground. If wiring is OK, repair or replace the air flow meter.