For 1990-2009 cars
Engine Controls Component Views
CMP and CKP Sensors
OBD II Symbol Description Notice
Ground Distribution Schematics
Powertrain Control Module Connector End Views
Powertrain Control Module Connector End Views
Handling ESD Sensitive Parts Notice
Ground Distribution Schematics

### Circuit Description

The camshaft position (CMP) actuator system enables the powertrain control module (PCM) to change the intake camshaft timing while the engine is running. The camshaft position (CMP) actuator solenoid valve controls the advance or retard of the camshaft. The CMP actuator solenoid is controlled by a pulse width modulated (PWM) signal from the PCM. The CMP sensor monitors the camshaft position or the camshaft angle, and compares that position or phase to the crankshaft position (CKP) senor signal. The PCM determines whether the camshaft angle is correct by comparing the actual camshaft position to the target camshaft position. By continuously analyzing the input of the CMP sensor and the CKP sensor the PCM can detect a fault in the CMP actuator system.

### Conditions for Running the DTC

• | The engine is running.

• | Engine coolant temperature is more than 70°C (158°F).

• | Vehicle speed is more than 8 km/h (5 mph).

### Conditions for Setting the DTC

• | The PCM does not detect a change in the camshaft timing when the CMP actuator solenoid is activated.

• | The PCM detects that the camshaft timing is fixed.

• | Either of the above conditions is present for at least 20 seconds.

### Action Taken When the DTC Sets

• | The PCM illuminates the malfunction indicator lamp (MIL) after 2 consecutive ignition cycles in which the diagnostic runs with the fault active.

• | The PCM stores the conditions that were present when the DTC set as Freeze Frame data.

### Conditions for Clearing the MIL/DTC

• | The PCM turns OFF the MIL on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.

• | A DTC clears after 40 consecutive warm-up cycles have occurred without a fault.

• | A DTC can be cleared by using the scan tool Clear DTC Information function.

### Diagnostic Aids

Inspect for any of the following conditions:

• | Inspect for any recent engine mechanical repairs. An incorrectly timed or incorrectly installed camshaft can cause a DTC P1349 to set.

• | If a DTC P1349 and P1346 are both present, inspect for a malfunctioning CMP solenoid valve. Observe that the Cam Phase Angle and Cam Phase Angle Desired parameters on a scan tool are approximately equal. A difference in the two parameters indicates that the CMP solenoid may be sticking.

• | An intermittent DTC P1349 can be caused by a loss in the oil supply to the CMP solenoid valve or the CMP actuator assembly. Inspect the oil passages for foreign material and blockage. Inspect the oil filter of the CMP actuator solenoid valve for dirt or restrictions. Refer to Camshaft Position Actuator Solenoid Valve Filter Replacement .

An intermittent malfunction may be caused by a fault in the electrical circuit of the CMP actuator valve. Inspect the wiring harness and components for an intermittent condition. Refer to Intermittent Conditions .

The information included in the Freeze Frame data can be useful in determining the vehicle operating conditions when the DTC first set.

### Test Description

The numbers below refer to the step numbers in the diagnostic table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. This step checks the operation of the CMP actuator system. When commanded ON, the CMP actuator solenoid advances the camshaft, usually causing the engine to stall.

3. This step visually inspects the operation of the CMP actuator solenoid valve. The solenoid plunger and spool valve movement should be smooth and rapid from extended to retracted.

4. This step checks for electrical resistance in the wiring and connections of the CMP actuator solenoid circuit. Circuit resistance as small as 25 ohms can cause the solenoid to malfunction and a DTC P1349 to set.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check
2 |

1. Disconnect the CMP actuator solenoid valve.
2. Measure the resistance of the solenoid with a digital multimeter (DMM).

Is the resistance within the specified range?

6.9-7.9 ohms at 20°C (68°F)

Go to Step 3

Go to Step 10

3 |

1. Connect the CMP solenoid valve.
2. Start the engine.
3. Allow the engine to reach a normal operating temperature.
4. Command the CMP actuator solenoid ON with the scan tool.

Does the engine idle very rough or stall when the CMP actuator solenoid is commanded ON with the scan tool?

--

Go to Diagnostic Aids

Go to Step 4

4 |

1. Remove the CMP actuator solenoid valve. Refer to Camshaft Position Actuator Solenoid Valve Replacement .
2. Connect the CMP actuator solenoid to B+ and ground with fused jumper wires.
3. Observe the movement of the solenoid plunger when electrical power is applied and released.

Does the solenoid plunger extend to at least the specified value when voltage is applied and then retract when voltage is removed?

3 mm (0.125 in

Go to Step 5

Go to Step 10

5 |

1. Remove the CMP actuator solenoid oil filter. Refer to Camshaft Position Actuator Solenoid Valve Filter Replacement .
2. Inspect the oil filter for restrictions or blockage.

Is the CMP actuator solenoid oil filter restricted or blocked?

--

Go to Step 9

Go to Step 6

6 |

1. Inspect the engine for correct valve timing. Refer to Valve Train Diagnosis .
2. Inspect the CMP actuator oil passages for blockage or restrictions.
3. Repair as necessary.

Was a repair necessary?

--

Go to Step 13

Go to Step 7

7 |

1. Install the CMP actuator solenoid valve. Refer to Camshaft Position Actuator Solenoid Valve Replacement .
2. Connect the CMP actuator solenoid.
3. Clear the DTC information with the scan tool.
4. Backprobe between the CMP acuator solenoid circuits with a DMM.
5. Start the engine.
6. Observe the DC voltage on the DMM while operating the CMP solenoid with the scan tool.

Was the voltage within the first specified value with the solenoid OFF, and within the second specified value with the solenoid ON?

0.7-1.0 volts

8.0-9.5 volts

Go to Step 11

Go to Step 8

8 |

1. Check the electrical circuit of the CMP actuator solenoid valve for high resistance in the circuit wiring or connections.
2. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

--

Go to Step 13

Go to Step 12

9 |

1. Clean or replace the CMP actuator solenoid filter. Refer to Camshaft Position Actuator Solenoid Valve Filter Replacement .
2. Install the CMP actuator solenoid valve. Refer to Camshaft Position Actuator Solenoid Valve Replacement .

Is the action complete?

--

Go to Step 13

-

10 | Replace the CMP actuator solenoid valve. Refer to Camshaft Position Actuator Solenoid Valve Replacement . Is the action complete? | -- | Go to Step 13 | --
11 | Replace the CMP actuator assembly. Refer to Timing Chain and Sprockets Removal . Is the action complete? | -- | Go to Step 13 | --
12 | Replace the PCM. Refer to Powertrain Control Module Replacement . Is the action complete? | -- | Go to Step 13 | --
13 |

1. Clear the DTC information with the scan tool.
2. Road test the vehicle within the Freeze Frame conditions that set the DTC
3. Review the scan tool data and check for DTCs.

Are any DTCs displayed on the scan tool?

--

Go to Diagnostic Trouble Code (DTC) List

System OK