For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC P0340: Intake Camshaft Position (CMP) Sensor Circuit
DTC P0341: Intake Camshaft Position (CMP) Sensor Performance
DTC P0366: Exhaust Camshaft Position (CMP) Sensor Performance

### Circuit/System Description

The CMP sensor is a hall effect switch that works in conjunction with a 4X reluctor wheel. The reluctor wheels are mounted to the camshaft position actuators that are mounted to the end of the camshafts. The ECM uses the CMP sensor signals in order to determine the position of the camshafts. The ECM supplies 5 volts to the CMP sensors on the 5-volt reference circuits, and supplies a ground on the low reference circuits. The CMP sensors provide a signal to the ECM on the signal circuits. If the ECM detects extra or missing CMP sensor signal transitions, or a signal voltage that is more or less than the predetermined range, within a certain number of crankshaft revolutions, one of these DTCs sets.

### Conditions for Running the DTC

• | The engine speed is running.

• | The DTCs run continuously once the above conditions are met for greater than 20 seconds.

### Conditions for Setting the DTC

The ECM detects an incorrect signal or no signal from the CMP sensor.

### Action Taken When the DTC Sets

DTC P0340, P0341, and P0366 are Type B DTCs.

### Conditions for Clearing the DTC

DTC P0340, P0341, and P0366 are Type B DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Electronic Ignition (EI) System Description

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Diagnostic Aids

The following conditions can also set the DTC:

• | Physical damage to the CMP sensor or the reluctor wheel

• | Excessive play or looseness of the CMP sensor or the reluctor wheel

• | Improper installation of the CMP sensor or the reluctor wheel

• | Foreign material passing between the CMP sensor and the reluctor wheel

• | Excessive air gap between the CMP sensor and the reluctor wheel

### Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTCs P0340, P0341, or P0366 should not set.
2. Move related harnesses/connectors of the CKP sensor and verify the engine does not stumble, stall, or change engine speed.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate camshaft position (CMP) sensor.
2. Ignition OFF, test for 5 ohms or less of resistance between the low reference circuit terminal 1 and ground.

⇒ | If greater than the specified range, test the low reference circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for greater than 4.8 volts between the 5V reference circuit terminal listed below and ground.

• | CMP Sensor Intake 5V reference circuit terminal 3

• | CMP Sensor Exhaust 5V reference circuit terminal 2

⇒ | If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal and the fuse is open, test all the components connected to the 5V reference circuit and replace as necessary.

4. Test for 4.8-5.2 volts between the signal circuit terminal listed below and ground.

• | CMP Sensor Intake 5V reference circuit terminal 2

• | CMP Sensor Exhaust 5V reference circuit terminal 3

⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.

5. If all circuits test normal, test or replace the CMP sensor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Camshaft Position Sensor Replacement

• | Control Module References for engine control module replacement, setup, and programming