The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor is used for ignition timing, fuel injector timing, misfire diagnostics, and tachometer display. The CKP sensor circuits are connected directly to the powertrain control module (PCM) and consists of the following circuits:
• | The 12-volt reference |
• | The low reference |
• | The medium resolution engine speed signal |
If the PCM detects no signal from the CKP sensor, DTC P0335 sets.
• | The camshaft position (CMP) sensor signal is incrementing. |
• | The mass air flow (MAF) is more than 5 g/s. |
• | The engine is cranking or running. |
The PCM has detected no CKP sensor pulses.
• | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
• | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/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.
Step | Action | Values | Yes | No | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | ||||||||||||||||
1 | Did you perform the Diagnostic System Check-Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||||||||
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 | ||||||||||||
Are DTCs P0335 and P0340 set? | -- | Go to Step 8 | Go to Step 5 | |||||||||||||
5 |
Is the voltage within the specified value? | B+ | Go to Step 6 | Go to Step 10 | ||||||||||||
6 | Measure the voltage from the 12-volt reference circuit to the low reference circuit of the CKP sensor with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage within the specified value? | B+ | Go to Step 7 | Go to Step 11 | ||||||||||||
7 |
Does the DMM display the specified value? | OL | Go to Step 16 | Go to Step 12 | ||||||||||||
Did you replace a component? | -- | Go to Step 20 | Go to Step 9 | |||||||||||||
Test the 12-volt reference circuit of each component for a short to ground. Refer to Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 13 | |||||||||||||
10 | Test the 12-volt reference 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 20 | Go to Step 14 | ||||||||||||
11 | Test the low reference circuit for the following conditions:
Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 14 | ||||||||||||
12 | Test the medium resolution engine speed signal circuit for the following conditions:
Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 14 | ||||||||||||
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 20 | Go to Step 14 | ||||||||||||
14 | 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 20 | Go to Step 15 | ||||||||||||
15 | Test for an intermittent and for a poor connection at the PCM. 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 20 | Go to Step 19 | ||||||||||||
16 |
Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 17 | ||||||||||||
17 | Inspect the reluctor wheel for the following conditions:
Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 18 | ||||||||||||
18 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 20 | -- | ||||||||||||
19 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 20 | -- | ||||||||||||
20 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 21 | ||||||||||||
21 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |