For 1990-2009 cars

### Circuit Description

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor is connected directly to the powertrain control module (PCM), and consists of the following circuits:

• | The 12-volt reference circuit

• | The low reference circuit

• | The CKP sensor signal circuit

If the PCM detects no signal from the CKP sensor for more than 3 seconds, DTC P0335 sets.

### Conditions for Running the DTC

• | DTCs P0101, P0102, P0103, P0341, P0342, or P0343 are not set.

• | The camshaft position (CMP) sensor is transitioning.

• | The mass air flow (MAF) is more than 3 g/s in the crank mode.

• | The MAF is more than 5 g/s in the running mode.

### Conditions for Setting the DTC

The PCM detects no signal from the CKP sensor for more than 3 seconds.

### 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.

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step determines if the fault is present.

2. This step simulates a CKP sensor signal to the PCM. If the PCM receives the signal, the fuel pump will operate for about two seconds.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain 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 | Go to Diagnostic System Check - Engine Controls
2 | Does the engine start and continue to run? | -- | Go to Step 3 | Go to Step 4
3 |

1. Observe the Freeze Frame/Failure Records for this DTC.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze/Frame Failure Records.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Intermittent Conditions

4 | Caution: Before proceeding, remove the fuses for the ignition coil and fuel injector feed circuits in order to prevent personal injury from engine rotation, sparks, and excessive engine fueling.

Important: An internally shorted CAM sensor can cause DTC P0335 to set. Test this circuit for a short before proceeding with this diagnostic table. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

1. Turn ON the ignition, with the engine OFF.
2. Disconnect the CKP sensor harness connector.
3. Measure the voltage from the CKP sensor 12-volt reference circuit to a good ground with the DMM.

Does the DMM display the specified value?

B+

Go to Step 5

Go to Step 7

5 | Measure the voltage between the CKP sensor 12-volt reference circuit and the CKP sensor low reference circuit with the DMM. Does the DMM display the specified value? | B+ | Go to Step 6 | Go to Step 8
6 | Momentarily connect the test lamp between the CKP sensor signal circuit and the CKP sensor 12-volt reference circuit. Does the fuel pump operate when voltage was applied to the CKP sensor signal circuit? | -- | Go to Step 11 | Go to Step 9
7 | Test for an open or a short to ground in the CKP sensor 12-volt reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 14
8 | Test for an open or for high resistance in the CKP sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 14
9 | Test the CKP sensor signal circuit for the following conditions:

• | High resistance

• | An open

• | A short to ground or low reference

• | A short to voltage or 12-volt reference

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 10

10 | Inspect for poor connections at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 14
11 |

1. Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement .
2. Visually inspect the CKP sensor for the following conditions:

• | Excessive play or looseness

• | Excessive air gap between the CKP sensor and the reluctor wheel

• | Physical damage

• | Foreign material passing between the CKP sensor and the reluctor wheel

• | Improper installation

• | Electromagnetic interference in the CKP sensor circuits

• | Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 12

12 | Inspect the CKP reluctor wheel for the following conditions:

• | Physical damage

• | Improper installation

• | Excessive endplay or looseness

| Refer to Crankshaft and Bearing Cleaning and Inspection in Engine Mechanical - 8.1L.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 13

13 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Did you complete the repair? | -- | Go to Step 16 | --
14 | Inspect for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 16 | Go to Step 15
15 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 16 | --
16 |

1. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze/Frame Failure Records.

Did the DTC run and pass?

--

Go to Step 17

Go to Step 2

17 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List | System OK