Circuit Description
The intake camshaft position (CMP) sensor is a hall integrated circuit (IC) type sensor that works in conjunction with an eight tooth reluctor wheel used to determine the position of the intake camshaft. The engine control module (ECM) supplies a 12-volt pull up voltage on the CMP sensor signal circuit. As the teeth on the reluctor wheel passes the CMP sensor, it sends a digital signal which is an image of the reluctor wheel to the ECM. The ECM processes this information to determine the exact position of the camshafts, and to determine the optimum ignition and injection points of the engine. The CMP sensor wiring consists of a 12-volt reference circuit, a low reference circuit and a signal circuit. If the ECM cannot see a change in the intake CMP sensor signal DTC P0340 or P0345 will set.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
The ECM does not detect a signal from the Intake CMP sensor after 10 seconds of engine run time.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | The following conditions may cause this DTC to set: |
| - | Damage to the camshaft reluctor wheel |
| - | Damage to the CMP sensor |
| - | The sensor coming in contact with the reluctor wheel |
| - | Foreign material passing between the sensor and the reluctor wheel |
| • | If the condition is intermittent, refer to Intermittent Conditions . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verifies that the condition is present.
-
This step determines if the signal circuit is shorted to voltage. A normal operating signal circuit will not illuminate a test lamp.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | ||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||
Did the DTC fail this ignition? | -- | Go to Step 3 | Go to Diagnostic Aids | |||||
3 |
Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 8 | ||||
4 |
Is the voltage more than the specified value? | 0.2 V | Go to Step 9 | Go to Step 5 | ||||
5 |
Is the voltage greater than the specified value? | 11 V | Go to Step 6 | Go to Step 10 | ||||
Probe the CMP sensor signal circuit with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 11 | Go to Step 7 | |||||
7 |
Is the resistance more than the specified value? | 5 ohms | Go to Step 12 | Go to Step 13 | ||||
8 | Test the 12-volt reference circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 14 | ||||
9 | Test the low reference circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 14 | ||||
10 | Test the CMP signal circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 14 | ||||
11 | Test the signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 14 | ||||
12 | Repair the high resistance in the signal circuit of the CMP sensor. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 18 | -- | ||||
13 | Test for an intermittent and for a poor connection at the CMP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 15 | ||||
14 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 17 | ||||
15 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 16 | ||||
16 | Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake or Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake . Did you complete the replacement? | -- | Go to Step 18 | -- | ||||
17 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 18 | -- | ||||
18 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 19 | ||||
19 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |||||
