Diagnostic Test

1) IAC MOTOR OPERATION
NOTE: If the engine will not idle, maintain an engine speed between 800 and 1500 RPM.

Start the engine.

Allow the engine to idle.

With a scan tool, read the IAC Current.

Is the IAC Current below 146 mA?

Yes
1. Go To 2).
No
1. Refer to the INTERMITTENT CONDITION diagnostic procedure.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
2) IAC MOTOR
Turn the ignition off.

Disconnect the IAC Motor harness connector.

Remove the IAC Motor.

NOTE: Inspect the IAC air passages for restrictions and damage to the IAC valve.

Measure the resistance across the IAC Motor pin terminals (component).

Is the resistance 9.7 +/- 1.0 ohms?

Yes
1. Go To 3).
No
1. Replace the IAC Motor.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
3) (K961) IAC RETURN CIRCUIT OPEN

Fig 1: MEASURING RESISTANCE OF THE IAC RETURN CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Disconnect the C2 PCM harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool No. 8815 to perform diagnosis.

Measure the resistance of the (K961) IAC RETURN circuit from the IAC Motor harness connector to the appropriate terminal of special tool No. 8815.

Is the resistance below 5.0 ohms?

Yes
1. Go To 4).
No
1. Repair the open in the (K961) IAC RETURN circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
4) (K961) IAC RETURN CIRCUIT SHORTED TO GROUND

Fig 2: MEASURING RESISTANCE BETWEEN GROUND AND THE IAC RETURN CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the (K961) IAC RETURN circuit in the IAC Motor harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (K961) IAC RETURN circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 5).
5) (K61) IAC MOTOR CONTROL CIRCUIT OPEN

Fig 3: MEASURING RESISTANCE OF THE IAC MOTOR CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (K61) IAC MOTOR CONTROL circuit from the IAC Motor harness connector to the appropriate terminal of special tool No. 8815.

Is the resistance below 5.0 ohms?

Yes
1. Go To 6).
No
1. Repair the open in the (K61) IAC MOTOR CONTROL circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
6) (K61) IAC MOTOR CONTROL CIRCUIT SHORTED TO GROUND

Fig 4: MEASURING RESISTANCE BETWEEN GROUND AND THE IAC MOTOR CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the (K61) IAC MOTOR CONTROL circuit in the IAC Motor harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (K61) IAC MOTOR CONTROL circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 7).
7) PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes
1. Repair as necessary.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE-POWERTRAIN CONTROL and STANDARD PROCEDURE - PCM/ECM/SKREEM PROGRAMMING .
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .