1224/2224 - Intake Air Temperature Sensor

Engine Management (DME M3.1, M50):

1. With the ignition switch in the "OFF" position, disconnect the intake air temp. sensor connector (X6205).
2. Turn the ignition switch to the run position and make the following voltage measurement at the female portion of the connector.

^ Gray wire (terminal 1), and ground = approx. 5 volts. If not, check wire to terminal 77 of at the Digital Motor Electronic (DME) control unit for an open or short to voltage or ground. If wire is OK, the DME control unit is defective.
^ If the voltage is correct continue with step 3.

3. With the ignition "OFF", disconnect the DME control unit connector; This cancels the DME fault codes. Be sure to take note of all fault codes before cancellation.
4. Install a new intake air temperature sensor, (known good unit).
5. Reconnect all harness connectors, start the engine and warm it up to operating temperature.

^ If the "Check Engine" light does not illuminate retain the new intake air temperature sensor.
^ If the "Check Engine" light illuminates and a fault code 1224 is present the DME control unit is defective.