Circuit Description
The engine control module (ECM) monitors the crankshaft position (CKP) and the camshaft position (CMP) signals to determine if they are synchronized. If both signals are not observed by the engine control module (ECM) within a narrow time window, the ECM will determine that an error has occurred and diagnostic trouble code (DTC) P1345 will set.
Conditions for Running the DTC
The engine is cranking or running.
Conditions for Setting the DTC
When the engine is cranking or running, the cam sensor pulses received by the ECM do not equal 3 or 0 per 2 crankshaft revolutions.
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
Check the following items:
| • | A loose CMP sensor causing a variance in the sensor signal. |
| • | Excessive free play or damage of the timing gears. |
| • | The Camshaft Reference Signal Missed parameter will only increment for an intermittent. A constant failure of the CMP sensor will not cause the parameter to increment, but will set DTC P0340. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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A condition that sets one of these DTCs may also result in a DTC P1345. Diagnose these codes before continuing with this diagnostic.
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This scan tool parameter will indicate 0 under normal conditions, and will cycle from 1 to 8 if a camshaft reference signal is missed (during intermittent conditions only). If this parameter reads anything except a constant 0 during the wiggle test, an intermittent wiring problem is indicated.
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A loose CMP sensor may result in a DTC P1345. Attempt to tighten the sensor to proper torque specifications. If unable to prevent CMP sensor movement, inspect the cover for damage before replacing the sensor.
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A cracked CMP sensor or internal breakage could result in DTC P1345. This will not be apparent unless the sensor is removed from the front engine cover. If the CMP sensor appears to be damaged by contact with the camshaft gear, it may be necessary to remove the front engine cover and inspect for excessive camshaft end-play. Refer to Camshaft Replacement in Engine Mechanical 6.6L.
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The wiggle test isolates the intermittent CMP sensor circuit to the harness or CMP connector.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |||||||
2 |
Does the DTC fail this ignition? | Go to Step 3 | Go to Intermittent Conditions | ||||||
Do any of the following DTCs set?
If one or more of these DTCs set, go to the appropriate table and diagnose that DTC first. | Go to Step 4 | ||||||||
Does the cam reference signal missed parameter increment? | Go to Step 8 | Go to Step 5 | |||||||
Inspect for a loose CMP sensor. If the sensor cannot be tightened, it must be replaced. Does the CMP sensor move without being able to be tightened? | Go to Step 9 | Go to Step 6 | |||||||
Does the CMP sensor show any signs of physical damage? | Go to Step 9 | Go to Step 7 | |||||||
7 |
Did you find and correct the condition? | Go to Step 10 | Go to Symptoms - Engine Mechanical in Engine Mechanical | ||||||
Inspect the circuits between the CMP sensor and the ECM for the following intermittent conditions:
Refer to Testing for Electrical Intermittents in Wiring Systems. Did you complete the repair? | Go to Step 10 | -- | |||||||
9 | Replace the camshaft position sensor. Refer to Camshaft Position Sensor Replacement . Did you complete the replacement? | Go to Step 10 | -- | ||||||
10 |
Does the DTC run and pass? | Go to Step 11 | Go to Step 2 | ||||||
11 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK | |||||||
