P0344-CAMSHAFT POSITION SENSOR INTERMITTENT SIGNAL PLAUSIBILITY

For a complete wiring diagram Refer to Section 8W

When Monitored:
With the engine speed between 20 and 6000 rpm.
Set Condition:
The ECM does not receive a Camshaft Position Sensor signal.

Possible Causes

5-VOLT SUPPLY CIRCUIT OPEN

CAMSHAFT POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE

CHECKING 5-VOLT SUPPLY CIRCUIT

DAMAGED CMP SENSOR OR CAMSHAFT

ECM

ECM - CAMSHAFT POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE

SENSOR GROUND CIRCUIT OPEN

INTERMITTENT CONDITION

CMP SENSOR SIGNAL CIRCUIT OPEN

5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND

CMP SENSOR SIGNAL CIRCUIT SHORTED TO GROUND

CMASHAFT POSITION SENSOR

ECM SENSOR GROUND CIRCUIT OPEN

5-VOLT SUPPLY CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT

CMP SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT

Diagnostic Test

1.VERIFY ACTIVE DTC

NOTE: If DTC P0641, P0651 or P0697 is present with this DTC, diagnose DTCs P0641, P0651 or P0697 before diagnosing this DTC.

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.

Does the scan tool display this DTC?

Yes

Go To 3

Go To 2

2.TEST DRIVE

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

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

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

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

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

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

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

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

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

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

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

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

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

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).