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For 1990-2009 cars only

Circuit Description

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.

Conditions for Running the DTC

    • 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.

Conditions for Setting the DTC

The PCM has detected no CKP sensor pulses.

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 Freeze Frame/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. An internally shorted camshaft position (CMP) sensor, crankshaft position (CKP) sensor or a short to ground on either 12-volt reference circuit will set DTCs P0335 and P0340.

  1. This step tests for an internally shorted CMP sensor or CKP sensor.

  1. This step tests for a short to ground on the 12-volt reference circuits of the CMP sensor or the CKP sensor.

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

  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

Are DTCs P0335 and P0340 set?

--

Go to Step 8

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Disconnect the crankshaft position (CKP) sensor.
  4. Measure the voltage from the 12-volt reference circuit of the CKP sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems.

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

  1. Turn OFF the ignition.
  2. Jumper the low reference circuit and the 12-volt reference circuit of the CKP sensor to the CKP harness connector with the J 35616 Terminal Test Kit. Refer to Circuit Testing in Wiring Systems.
  3. Measure the D.C. duty cycle from the signal circuit of the CKP sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems.
  4. Crank the engine.

Does the DMM display the specified value?

OL

Go to Step 16

Go to Step 12

8

  1. Measure the voltage from the 12-volt reference circuit of the CKP sensor and the camshaft position (CMP) sensor with a DMM while disconnecting the sensors one at a time. Refer to Circuit Testing in Wiring Systems.
  2. If the voltage changes when one of the above components are disconnected, replace the component. Refer to the appropriate replacement procedure.

Did you replace a component?

--

Go to Step 20

Go to Step 9

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:

    • An open
    • High resistance
    • A short to voltage
        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

12

Test the medium resolution engine speed signal circuit for the following conditions:

    • An open
    • High resistance
    • A short to voltage
    • A short to ground
        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

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

  1. Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement .
  2. Visually inspect the CKP sensor for the following conditions:
  3. • Physical damage
    • Excessive play or looseness
    • Improper installation
    • Foreign material passing between the CKP sensor and the reluctor wheel
    • Excessive air gap between the CKP sensor and the reluctor wheel
    • Electromagnetic interference in the CKP sensor circuits

Did you find and correct the condition?

--

Go to Step 20

Go to Step 17

17

Inspect the reluctor wheel for the following conditions:

    • Physical damage
    • Excessive end play or looseness
    • Improper installation
        Refer to Crankshaft and Bearing Cleaning and Inspection in Engine Mechanical - 3.5L.

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

  1. Lower the vehicle.
  2. Clear the DTCs with a scan tool.
  3. Turn OFF the ignition for 30 seconds.
  4. Start the engine.
  5. 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 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