Test Procedure
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
- JD1 CHECK THE CKP SENSOR SIGNAL TO THE PCM NOTE: With electronic throttle control (ETC), erroneous ignition and ETC-related diagnostic trouble codes (DTCs) may be set due to salt water intrusion into the CKP sensor harness connector. These DTCs are set in the following combination:
- P0320 and P0351
Thoroughly clean the connector, pack with di-electric grease and retest. If the problem returns, continue the CKP sensor diagnosis.
- Battery fully charged and starting system functioning properly.
- Key ON, engine OFF.
- Access the PCM and monitor the RPM PID.
- Crank the engine using the engine cranking diagnostic mode. Refer toDIAGNOSTIC MODES .
- Is the engine speed between 900-1,200 RPM?
Yes No The CKP, PCM, and harness are working properly.
RETURN to the SYMPTOM CHARTS article, Symptom Charts for further direction.GO to JD2. - JD2 CHECK THE TIMING COVER, CKP SENSOR, AND CRANKSHAFT PULSE WHEEL FOR OBVIOUS PHYSICAL DAMAGE
- Key in OFF position.
- Visually check the timing cover, CKP sensor, and crankshaft pulse wheel (outside the timing cover) for obvious physical damage.
- Do any parts appear physically damaged?
Yes No REPAIR or INSTALL a new component as necessary.
CLEAR the DTCs. REPEAT the self-test.GO to JD3. - JD3 CHECK FOR PROPER CKP BIAS VOLTAGES IN THE PCM
- CKP Sensor connector disconnected.
- Key ON, engine OFF.
- Measure the voltage between:
( + ) CKP Sensor Connector, Harness Side ( - ) Vehicle Battery CKP+ - Pin 1 Negative terminal CKP- - Pin 2 Negative terminal - Are the voltages between 1 - 3 V?
Yes No GO to JD4. GO to JD6. - JD4 CHECK THE CKP SENSOR RESISTANCE NOTE: The CKP sensor resistance values change significantly with temperature rise.
- Key in OFF position.
- Measure the resistance between:
( + ) CKP Sensor Connector, Component Side ( - ) CKP Sensor Connector, Component Side CKP+ - Pin 1 CKP- - Pin 2 - Is the resistance between 250 - 1K ohms?
Yes No GO to JD5. INSTALL a new CKP sensor. CLEAR the DTCs. REPEAT the self-test. - JD5 CHECK THE CKP HARNESS SHIELD GROUND NOTE: The harness shield protects the CKP signal from electrical noise and is grounded at one end, typically near the PCM.NOTE: Carry out the following resistance measurement between the CKP shield and the chassis ground.
- Measure the resistance between:
( + ) CKP_SHLD Assembly Connector, Harness Side ( - ) CKP_SHLD Ground - Is the resistance less than 5 ohms?
Yes No GO to JD6. REPAIR the circuit. CHECK for a poor ground connection.
CLEAR the DTCs. REPEAT the self-test. - Measure the resistance between:
- JD6 CHECK FOR A SHORT BETWEEN THE CKP(+) AND CKP(-) IN THE HARNESS
- PCM connector disconnected.
- Measure the resistance between:
( + ) CKP Sensor Connector, Harness Side ( - ) CKP Sensor Connector, Harness Side CKP+ - Pin 1 CKP- - Pin 2 - Is the resistance greater than 10K ohms?
Yes No GO to JD7. REPAIR the circuit.
CLEAR the DTCs. REPEAT the self-test. - JD7 CHECK THE CKP CIRCUIT(S) FOR AN OPEN IN THE HARNESS
- PCM connector disconnected.
- Measure the resistance between:
( + ) CKP Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side CKP- - Pin 2 CKP- - Pin E45 CKP+ - Pin 1 CKP+ - Pin E34 - Are the resistances less than 5 ohms?
Yes No GO to JD8. REPAIR the circuit.
CLEAR the DTCs. REPEAT the self-test. - JD8 CHECK THE CKP CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS
- Key ON, engine OFF.
- Measure the voltage between:
( + ) PCM Connector, Harness Side ( - ) Vehicle Battery CKP+ - Pin E34 Negative terminal CKP- - Pin E45 Negative terminal - Is any voltage present?
Yes No REPAIR the circuit.
CLEAR the DTCs. REPEAT the self-test.GO to JD9. - JD9 CHECK THE CKP CIRCUIT(S) FOR A SHORT TO GROUND IN THE HARNESS
- Key in OFF position.
- Measure the resistance between:
( + ) CKP Sensor Connector, Harness Side ( - ) Vehicle Battery CKP+ - Pin 1 Negative terminal CKP- - Pin 2 Negative terminal - Are the resistances less than 10K ohms?
Yes No REPAIR the circuit.
CLEAR the DTCs. REPEAT the self-test.GO to JD10. - JD10 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test and verify the concern is still present.
- Is the concern still present?
Yes No INSTALL a new PCM. REFER toFLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.