NOTE: The Timing Belt/Chain must be correctly installed and operational before diagnosis can be made. Refer to the Service Information to ensure the timing belt is properly installed.

NOTE: If the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.

NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.

Turn the ignition on.
With the scan tool, erase the ECM DTCs.
Attempt to start the engine cranking the engine for at least 7 seconds.
With the scan tool, read the ECM DTCs.

Does the scan tool display this DTC?

Yes

Go To 3

Go To 2

2. TEST DRIVE

Turn the ignition on.
With the scan tool, erase the ECM DTCs.
Test drive the vehicle.
With the scan tool, read the ECM DTCs.

Does the scan tool display this DTC?

Yes

Go To 3

Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

3. CHECKING CAMSHAFT POSITION SENSOR SIGNAL CKT

Turn the ignition off.
Disconnect the Camshaft Position Sensor harness connector.
Turn the ignition on.
Measure the voltage of the CMP Sensor Signal circuit.

Select the appropriate voltage reading.

Voltage is above 5.4 volts.

Go To 4

Voltage is between 4.7 and 5.4 volts.

Go To 5

Voltage is below 4.7 volts.

Go To 13

4. CAMSHAFT POSITION SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE

Turn the ignition off.
Disconnect the ECM harness connectors.
Remove the ASD Relay.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay connector.
Turn the ignition on.
Measure the voltage of the CMP Position Sensor Signal circuit.

Is the voltage below 1.0 volt?

Yes

Replace and program the Engine Control Module in accordance with the Service Information.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Repair the Camshaft Position Sensor Signal circuit for a short to voltage.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

5. CHECKING 5-VOLT SUPPLY CIRCUIT

Measure the voltage of the CMP Sensor 5-Volt Supply circuit.

Select the appropriate voltage reading.

Voltage is above 5.4 volts.

Repair the CMP 5-Volt Supply circuit for a short to voltage.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Voltage is between 4.7 and 5.4 volts.

Go To 6

Voltage is below 4.7 volts.

Go To 10

6. SENSOR GND CKT OPEN

Turn the ignition off.
Disconnect the ECM harness connectors.
Measure the resistance of the Sensor Ground circuit between the CMP Sensor harness connector and the ECM harness connector.

Is the resistance below 10.0 ohms?

Yes

Go To 7

Repair the Sensor Ground circuit for an open.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

7. ECM - SENSOR GROUND CIRCUIT OPEN

Turn the ignition on.
Disconnect the ECT Sensor harness connector.
Disconnect the Camshaft Position Sensor harness connector.
Connect one end of a jumper wire to the ECT Sensor signal circuit in the ECT Sensor harness connector.
Connect the other end of the jumper wire to the Sensor Ground circuit in the Camshaft Position Sensor harness connector.
With the scan tool read the Engine Coolant Temp volts.

Is the voltage below 0.5 volt?

Yes

Go To 8

Replace and program the ECM in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

8. DAMAGED CMP SENSOR OR CAMSHAFT

Turn the ignition off.
Remove the CMP Sensor.
Inspect the CMP Sensor for conditions such as loose mounting screws, damage, or cracks.
Inspect the camshaft for conditions such as damage, debris or cracked teeth.

Is there any evidence of these conditions?

Yes

Repair as necessary.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Go To 9

9. CAMSHAFT POSITION SENSOR

Turn the ignition off.
With the ab scope lead, backprobe the CMP Signal circuit.
While observing the lab scope display, crank the engine.

Does the lab scope display an uninterrupted digital signal (square wave)?

Yes

Replace and program the Engine Control Module in accordance with the Service Information.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Replace the Camshaft Position Sensor in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

10. 5-VOLT SUPPLY CIRCUIT OPEN

Turn the ignition off.
Disconnect the ECM harness connectors.
Measure the resistance of the 5-Volt Supply circuit between the ECM harness connector and the CMP Sensor harness connector.

Is the resistance below 10.0 ohms?

Yes

Go To 11

Repair the 5-Volt Supply circuit for an open.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

11. 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the CMP Sensor 5-Volt Supply circuit.

Is the resistance above 1000 ohms?

Yes

Go To 12

Repair the CMP Sensor 5-Volt Supply circuit for a short to ground.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

12. 5-VOLT SUPPLY CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT

Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between the CMP Sensor 5-Volt Supply circuit and the Sensor Ground circuit at the CMP Sensor harness connector.

Is the resistance above 1000 ohms?

Yes

Replace and program the Engine Control Module in accordance with the Service Information.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Repair the CMP Sensor 5-Volt Supply and Sensor Ground circuits for a short together.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

13. CMP SENSOR SIGNAL CIRCUIT OPEN

Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the CMP Sensor Signal circuit.

Is the resistance below 10.0 ohms?

Yes

Go To 14

Repair the CMP Sensor Signal circuit for an open
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

14. CMP SENSOR SIGNAL CIRCUIT SHORTED TO GROUND

Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the CMP Sensor Signal circuit.

Is the resistance below 1000 ohms?

Yes

Repair the CMP Sensor Signal circuit for a short to ground.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Go To 15

15. CMP SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT

Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between the CMP Sensor Signal circuit and the Sensor Ground circuit at the CMP Sensor harness connector.

Is the resistance below 1000 ohms?

Yes

Repair the CMP Sensor Signal and Sensor Ground circuits for a short together.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Replace and program the Engine Control Module in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).