For 1990-2009 cars

### Circuit Description

The crankshaft position (CKP) sensor is located on the rear of bank 1 of the engine block. The CKP sensor produces an AC voltage of different amplitude and frequency depending on the velocity of the crankshaft. The CKP sensor works in conjunction with a 58X reluctor wheel that is attached to the crankshaft. Each tooth on the reluctor wheel is spaced 6 degrees apart with one span having a 12-degree space. The engine control module (ECM) uses the 12-degree space to determine top dead center for cylinders 1 and 4. The ECM determines when cylinder 1 is on the compression stroke by monitoring the CKP sensor and the camshaft position (CMP) sensors. The ECM can synchronize the ignition timing, fuel injector timing, and spark knock control based on the CKP sensor and the CMP sensor inputs. If the ECM loses the cylinder 1 crankshaft reference position and must re-sync the engine position, this DTC sets.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0336 Crankshaft Position (CKP) Sensor Performance

### Conditions for Running the DTC

• | The engine is cranking or operating.

• | DTC P0336 runs continuously once the above conditions are met for approximately 5 seconds.

### Conditions for Setting the DTC

• | The ECM re-syncs the engine position 6 or more times during an ignition cycle.

| OR

• | The ECM detects 28 or more interruptions in the engine speed signal during an ignition cycle.

• | The above condition exists for more than 4 seconds.

### Action Taken When the DTC Sets

• | 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 Failure Records.

### Conditions for Clearing the MIL/DTC

• | The control module turns OFF the malfunction indicator lamp (MIL) after 4 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

• | Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. Using this kit prevents damage to the harness or component terminals.

• | The lower connector of the ECM is connector C1 and the upper connector of the ECM is connector C2. Refer to Front of Vehicle/Engine Compartment Component Views.

• | The ECM uses the camshaft position sensors to determine engine speed and position when there is a CKP sensor condition.

• | The engine will operate with a CKP sensor condition only if the ECM has stored the learned reference position of the camshafts in memory. With a crankshaft position sensor condition other than a short to voltage in the signal circuit, the engine will go into a limp home mode after a hard restart. The ECM then calculates engine speed from one of the camshaft position sensors. During a limp home mode the following additional DTCs may set and should be ignored:

- | DTC P0324 Knock Sensor (KS) Module Performance

- | DTC P1011 Intake Camshaft Position Actuator Park Position Bank 1

• | The following conditions may cause this DTC to set:

- | An intermittent condition in the CMP sensor circuits can cause a CKP DTC to set. Inspect the CMP sensor, harness connections, and related wiring, if you suspect this condition.

- | Intermittent short to ground in the signal circuit

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

- | CKP sensor damage or improper installation

- | Crankshaft reluctor wheel damage or improper installation

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

• | Excess crankshaft end play causes the reluctor wheel to move out of alignment with the CKP sensor. This could result in any one of the following conditions:

- | A hard start

- | A start and stall

- | Erratic performance

• | For an intermittent condition, refer to Intermittent Conditions.

### Test Description

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

1. This step is testing for a poor connection at the components and for an intermittent condition with the wiring. Clearing the DTCs allows the ECM to synchronize the cam and crank reference pulses.

2. This step is testing for electromagnetic interference (EMI). If the CKP sensor circuits are routed close to high load circuits or components, this DTC may set.

3. This step is testing if the CKP sensor is installed correctly. A CKP sensor that is not fully seated, may cause this DTC to set.

4. This step is testing for an ECM condition. The ECM uses a pull-up voltage of 2.5 volts on each CKP sensor circuit to reduce noise interference from EMI. If the voltage is not present, replace the ECM.

5. This step is testing for an ECM condition. The ECM uses a pull-up voltage of 2.5 volts on each CKP sensor circuit to reduce noise interference from EMI. If the voltage is not present, replace the ECM.

6. This step tests for a condition in the CKP sensor ground shield. Normal EMI could effect the out-put signal of the CKP sensor if the shield is shorted to the other circuits of the CKP sensor, or grounded externally of the ECM.

7. Missing, damaged, or broken teeth on the reluctor wheel can set this DTC. If the crankshaft was recently replaced or the vehicle/engine is new and this DTC is set, inspect all teeth on the reluctor wheel.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Engine Controls Schematics Connector End View Reference: Component Connector End Views
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Note: An intermittent condition in the camshaft position (CMP) sensor circuits could cause a CKP DTC to set. Refer to the Diagnostic Trouble Code (DTC) List - Vehicle , if there are any CMP sensor DTCs stored.

1. Start the engine.
2. Observe the DTC Info with a scan tool.

Does the DTC fail this ignition?

--

Go to Step 4

Go to Step 3

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 Diagnostic Aids

4 | Is DTC P0335 also set? | -- | Go to DTC P0335 | Go to Step 5
5 |

1. Clear any DTCs with a scan tool.
2. Start the engine.
3. Raise the engine speed to 1,000 RPM for 30 seconds.
4. Allow the engine to idle.
5. Move the related harnesses and connectors for the CKP sensor from the engine control module (ECM) to the CKP sensor.

Does the engine stumble or stall when moving the harnesses and connectors?

--

Go to Step 15

Go to Step 6

6 |

1. Turn OFF the ignition.
2. Inspect the crankshaft position (CKP) sensor circuits for the following conditions:

• | Routed too close to the battery or the battery cables

• | Routed too close to other wiring or components

• | Routed too close to after market add on electrical equipment

• | Routed too close to solenoids, relays, and motors

3. Repair the condition as necessary.

Did you find and correct the condition?

--

Go to Step 19

Go to Step 7

7 |

1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
2. Inspect the CKP sensor for being installed correctly. Make sure the CKP sensor fastener is torqued to the specified value.

Did you find and correct the condition?

8 N·m (71 lb in)

Go to Step 19

Go to Step 8

8 |

1. Disconnect the CKP sensor.
2. Turn the ignition switch to ON position, with the engine OFF.
3. Measure the voltage between the low reference circuit of the CKP sensor and a good ground with a DMM.

Is the voltage within the specified range?

2-3 V

Go to Step 9

Go to Step 14

9 | Measure the voltage between the signal circuit of the CKP sensor and a good ground with a DMM. Is the voltage within the specified range? | 2-3 V | Go to Step 10 | Go to Step 14
10 |

1. Turn OFF the ignition.
2. Disconnect the ECM.
3. Measure the resistance between the engine ground shield circuit of the CKP sensor, at the ECM connector, and the ECM housing.

Is the resistance less than the specified value?

5 Ω

Go to Step 11

Go to Step 16

11 |

1. Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement.
2. Inspect the CKP sensor for damage.

Is the CKP sensor damaged?

--

Go to Step 12

Go to Step 13

12 | Note: If the reluctor wheel is also damaged, replace the CKP sensor and the crankshaft. Inspect the reluctor wheel for damage. Is the reluctor wheel damaged? | -- | Go to Crankshaft and Bearing Cleaning and Inspection | Go to Step 17
13 | 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. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 17
14 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 18
15 | Repair the intermittent condition in the CKP sensor circuits. Refer to Wiring Repairs. Did you complete the repair? | -- | Go to Step 19 | --
16 | Repair the open or high resistance in the engine ground shield. Refer to Wiring Repairs. Did you complete the repair? | -- | Go to Step 19 | --
17 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement. Did you complete the replacement? | -- | Go to Step 19 | --
18 | Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 19 | --
19 |

1. Clear any 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 fail this ignition?

--

Go to Step 2

Go to Step 20

20 | 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 | System OK