The camshaft position (CMP) sensor is installed on the cylinder head at the rear of the camshaft gear. The CMP sensor has the following circuits:
• | A 12-volt reference circuit |
• | A CMP sensor signal circuit |
The engine control module (ECM) supplies 12 volts to the CMP sensor on the 12-volt reference circuit. The CMP sensor provides a signal to the ECM on the CMP signal circuit. The CMP sensor detects a total of 7 through holes, 6 holes arranged equally at every space, and one reference hole on the camshaft gear flange surface, and sends signals to the ECM. Receiving these signals, the ECM determines cylinder #1 compression top dead center (TDC). If the ECM detects the CMP sensor signals are not generated, this DTC will set.
This diagnostic procedure supports the following DTC:
DTC P0385 Crankshaft Position (CKP) Sensor B Circuit
The crankshaft speed sensor signal is OK.
The camshaft speed sensor signals are not generated during 10 engine rotations.
• | The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
• | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
• | The MIL resets when the ignition is turned OFF. |
• | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
• | Clear the MIL and the DTC with a scan tool. |
Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |||||||
2 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 3 | ||||||
3 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 4 | ||||||
4 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 5 | ||||||
5 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 6 | ||||||
6 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 7 | ||||||
7 |
Did the DTC fail this ignition? | Go to Step 8 | Go to Intermittent Conditions | ||||||
8 | Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement . Did you complete the replacement? | Go to Step 9 | -- | ||||||
9 |
Did the DTC fail this ignition? | Go to Step 10 | Go to Step 12 | ||||||
10 |
Important: The new ECM must be programmed. Replace the ECM. Refer to Engine Control Module Programming and Setup , Engine Control Module Replacement/Restore Fuel Rate Data , and Fuel Injector Flow Rate Programming . Did you complete the replacement? | Go to Step 11 | -- | ||||||
11 |
Did the DTC fail this ignition? | Go to Step 2 | Go to Step 12 | ||||||
12 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK |