TEST
ACTION
APPLICABILITY
5
Turn the ignition off.
Disconnect the MAF Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance between the MAF Signal circuit and the ASD Relay Output
circuit in the MAF Sensor harness connector.
Is the resistance below 100 ohms?
All
Yes
→ Repair the MAF Signal circuit for a short to the ASD Relay
Output circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 6
6
Turn the ignition off.
Disconnect the MAF Sensor harness connector.
Disconnect the PCM harness connector.
Ignition on, engine not running.
Measure the voltage of the MAF Signal circuit in the MAP Sensor harness connector.
Is any voltage present?
All
Yes
→ Repair the short to battery voltage in the MAF Signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 7
7
Turn the ignition off.
Disconnect the MAF Sensor harness connector.
Disconnect the PCM harness connector.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the MAF Signal circuit from the MAF Sensor harness
connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?
All
Yes
→ Go To 8
No
→ Repair the open in the MAF Signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
8
Turn the ignition off.
Disconnect the MAF Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance between ground and the MAF Signal circuit at the MAF
Sensor harness connector.
Is the resistance below 100 ohms?
All
Yes
→ Repair the short to ground in the MAF Signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 9
205
DRIVEABILITY - NGC
P0491-AIR INJECTION SYSTEM PERFORMANCE —
Continued