The crankshaft position (CKP) sensor is a variable reluctance sensor. The CKP sensor indicates the crankshaft speed and position. The CKP sensor produces an AC voltage of different amplitude and frequency. The frequency depends on the velocity of the crankshaft. The AC voltage output depends on the CKP and battery voltage. The engine control module (ECM) uses a pull-up voltage of 2.5 volts on each CKP sensor circuit for reduction of noise interference from electromagnetic generating devices. The CKP sensor works in conjunction with a 58-tooth reluctor wheel on the crankshaft. The CKP sensor connects to the ECM through the following circuits:
• | A CKP sensor high circuit |
• | A CKP sensor low circuit |
If the ECM detects no signal, DTC P0335 sets.
• | DTCs P0341, P0342, P0343 are not set. |
• | The engine is cranking or running |
The ECM has detected no CKP sensor pulses.
• | 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. |
• | 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. |
The numbers below refer to the step numbers on the diagnostic table.
This step tests for an internally shorted CKP sensor.
This step tests for a short to voltage in the battery circuit.
This step tests for a short to voltage in the battery circuit.
This step tests for a short to voltage in the ignition circuit.
This step tests for a short to voltage in the ignition circuit.
Step | Action | Values | Yes | No | ||||||||||||
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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 | |||||||||||||
2 | Attempt to start the engine. Does the engine start and run? | -- | Go to Step 3 | Go to Step 4 | ||||||||||||
3 |
Did the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions | ||||||||||||
Is the resistance within the specified range? | 800-1200 ohms | Go to Step 5 | Go to Step 19 | |||||||||||||
Measure the voltage from the high circuit of the CKP sensor harness connector to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage more than the specified value? | 4 V | Go to Step 12 | Go to Step 6 | |||||||||||||
Measure the voltage from the low circuit of the CKP sensor harness connector to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage more than the specified range? | 4 V | Go to Step 13 | Go to Step 7 | |||||||||||||
Is the voltage more than the specified value? | 4 V | Go to Step 12 | Go to Step 8 | |||||||||||||
Measure the voltage from the low circuit of the CKP sensor harness connector to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage more than the specified value? | 4 V | Go to Step 13 | Go to Step 9 | |||||||||||||
9 | Measure the voltage from the high circuit of the CKP sensor harness connector to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage less than the specified value? | 2 V | Go to Step 14 | Go to Step 10 | ||||||||||||
10 | Measure the voltage from the low circuit of the CKP sensor harness connector to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage less than the specified value? | 2 V | Go to Step 15 | Go to Step 11 | ||||||||||||
11 |
Does the DMM display the specified value? | OL | Go to Step 17 | Go to Step 16 | ||||||||||||
12 | Test the high 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 23 | Go to Step 17 | ||||||||||||
13 | Test the low 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 23 | Go to Step 17 | ||||||||||||
14 | Test the high circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 17 | ||||||||||||
15 | Test the low circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 17 | ||||||||||||
16 | Test the high circuit shorted to the low circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 17 | ||||||||||||
17 | Test for an intermittent and for a poor connection at the CKP 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 23 | Go to Step 18 | ||||||||||||
18 | 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 23 | Go to Step 22 | ||||||||||||
19 |
Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 20 | ||||||||||||
20 | Inspect the reluctor wheel for the following conditions:
Refer to Crankshaft and Bearing Cleaning and Inspection in Engine Mechanical Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 21 | ||||||||||||
21 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- | ||||||||||||
22 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- | ||||||||||||
23 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 24 | ||||||||||||
24 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK |