Test Procedure
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2005 Mercury Sable, 2005 Mercury Mountaineer, 2005 Mercury Monterey, 2005 Mercury Montego, and 2005 Mercury Mariner. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION table of fault code setting condition.
FAULT CODE SETTING CONDITION
| Fault Code | Application | Setting Condition | Testing |
|---|---|---|---|
| P0351, P0352, P0353, P0354 | Coil-on-plug (COP) ignition | KOER, Continuous Memory | JF1 |
| P0351, P0352, P0353, P0354 | Coil pack ignition testing | KOER, Continuous Memory | JE1 |
| P0355, P0356, P0357, P0358, P0359, P0360 | All | KOER, Continuous Memory | JF1 |
- JE1 DETERMINE WHICH COIL IS NOT FIRING PROPERLY NOTE: Electronic ignition engine timing is entirely controlled by the PCM. Electronic ignition timing is NOT adjustable. Do not attempt to check base timing. You will receive false readings.
- Record the suspect cylinder, coil and PCM pin number from the table.
- Determine which coil is not firing properly using the information from Pinpoint Test JB or a DTC and the table at the beginning of this pinpoint test.
- Record the suspect cylinder, coil and PCM pin number from the table.
Have the suspect cylinder number, coil driver and PCM pin number been recorded?
Yes No GO to JE2. To obtain the required information, repeat step JE1. - JE2 DTC P0351, P0352, P0353: CHECK IGN START/RUN VOLTAGE TO THE COIL PACK
- Disconnect the suspect coil, as determined from the table.
- Key in ON position.
- Measure the voltage between the IGN START/RUN circuit at the coil pack harness connector and ground.
Is the voltage greater than 10 volts?
Yes No Key in OFF position.
GO to JE3.IGN START/RUN circuit fault KEY OFF.
CHECK the condition of the related fuses/ fuse links. If OK, REPAIR the open circuit. If the fuse/fuse link is damaged, CHECK the IGN
START/RUN circuit for short to ground. REPAIR as necessary. CARRY OUT the misfire monitor drive cycle. REFER to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE . - JE3 CHECK THE FUNCTIONALITY OF THE SUSPECT COIL DRIVER (CD) CIRCUIT
- Connect an test lamp between IGN START/RUN and the suspect CD circuit (determined from the table) at the coil pack harness connector.
- Locate and activate the fuel inertia switch to disable the fuel pump.
- Observe the test lamp while cranking the engine.
Did the test lamp blink consistently?
Yes No Key in OFF position.
GO to JE7.Key in OFF position.
GO to JE4. - JE4 CHECK THE SUSPECT CD CIRCUIT FOR AN OPEN IN THE HARNESS
- Disconnect the PCM.
- Measure the resistance of the suspect CD circuit between the PCM harness connector pin (as determined from the table) and the coil pack connector.
Is the resistance less than 5 ohms?
Yes No GO to JE5. REPAIR the open circuit. CARRY OUT the misfire monitor drive cycle. REFER to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE . - JE5 CHECK THE SUSPECT CD CIRCUIT FOR A SHORT TO VPWR IN THE HARNESS
- Key in ON position.
- Measure the voltage between the suspect CD circuit at the PCM harness connector (as determined from the table) and ground.
Is the voltage less than 1 volt?
Yes No Key in OFF position.
GO to JE6.Key in OFF position. REPAIR the short circuit.
CARRY OUT the misfire monitor drive cycle. REFER to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE . - JE6 CHECK THE SUSPECT CD CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS
- Disconnect the diagnostic tool.
- Measure the resistance between the suspect CD circuit at the PCM harness connector (as determined from the table) and ground.
Is the resistance greater than 10K ohms?
Yes No Install a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . REPAIR the short circuit. CARRY OUT the misfire monitor drive cycle. REFER to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE . - JE7 CHECK THE SUSPECT COIL FOR DAMAGE
- Remove the spark plug wire from the suspect coil tower (as determined from the table).
- Connect the air gap spark tester 303-DO37 (D81P-6666-A) or its equivalent in series between the suspect coil tower and the spark plug wire.
- Disable the inertia switch.
- Observe the spark tester while cranking the engine.
Is a bluish-white spark present?
Yes No Key in OFF position.
GO to PINPOINT TEST Z STEP 1 .INSTALL a new coil pack as needed. CARRY OUT the misfire monitor drive cycle. REFER to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE .