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 that the CKP sensor signal is incorrect for more than 120 seconds, DTC P0336 sets.

### Conditions for Running the DTC

The engine is cranking or running.

### Conditions for Setting the DTC

The PCM determines that the CKP sensor signal is out of range for more than 120 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 verifies that the malfunction is present.

2. This step tests for electromagnetic interference (EMI) on the CKP sensor circuits.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views and Powertrain Control Module 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 | Important: If DTC P0335 is also set, diagnose DTC P0335 before proceeding with this DTC.

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 3

Go to Intermittent Conditions

3 | Inspect all of the crankshaft position sensor (CKP) circuits for the following conditions:

• | Wiring routed too closely to secondary ignition wires or components

• | Wiring routed too closely to after-market add-on electrical equipment

• | Wiring routed to closely to solenoids, relays, and motors

• | Electromagnetic interference in the CKP sensor circuits

Did you find and correct the condition?

--

Go to Step 12

Go to Step 4

4 | Test the 12-volt reference circuit for an intermittent condition or shorted to other circuits. Refer to Testing for Electrical Intermittents and Inducing Intermittent Fault Conditions in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 5
5 | Test the low reference circuit for an intermittent condition. Refer to Testing for Electrical Intermittents and Inducing Intermittent Fault Conditions in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 6
6 | Test the CKP sensor signal circuit for an intermittent condition. Refer to Testing for Electrical Intermittents and Inducing Intermittent Fault Conditions in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 7
7 | Test for an intermittent and for a poor connection at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 8
8 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9
9 | Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Inspect the CKP sensor for the following conditions:

• | Physical damage

• | Improper installation

• | Excessive play or looseness

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

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

• | Insufficient fuel

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

10 | Inspect the reluctor wheel for the following conditions:

• | Physical damage

• | Improper installation

• | Excessive endplay or looseness

Refer to Crankshaft and Bearing Installation in Engine Mechanical - 8.1L.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

11 | Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 12 | --
12 |

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 fail this ignition?

--

Go to Step 2

Go to Step 13

13 | 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