Test Procedure

NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION table of fault code setting condition.

FAULT CODE SETTING CONDITION

Fault Code	KOER	Continuous Memory
P0351	JF1	JF1
P0352	JF1	JF1
P0353	JF1	JF1
P0354	JF1	JF1
P0355	JF1	JF1
P0356	JF1	JF1
P0357	JF1	JF1
P0358	JF1	JF1
P0359	JF1	JF1
P0360	JF1	JF1

JF1 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.

Determine which coil is not firing properly using the information from Pinpoint Test JB or a DTC and the IGNITION COIL TO CYLINDER CORRELATION table at the beginning of this pinpoint test.
Record the suspect cylinder, coil and PCM pin number from the IGNITION COIL TO CYLINDER CORRELATION table.

Have the suspect cylinder number, coil driver and PCM pin number been recorded?

Yes	No
GO to JF2.	REPEAT the test step to obtain the required information.

JF2 CHECK THE FUNCTIONALITY OF THE SUSPECT COIL DRIVER (CD) CIRCUIT

NOTE: On certain applications with Electronic Throttle Control (ETC), erroneous ignition and ETC related DTCs may be set due to salt water intrusion into the CKP harness connector. These DTCs are: P0320, P0351, P0356 and P2106. Thoroughly clean the connector, pack with di-electric grease and retest. If the problem returns, REPLACE the CKP sensor.

Suspect Coil connector disconnected.
Connect the incandescent test lamp between IGN START/RUN and the Coil Driver (CD) A circuit at the coil on plug harness connector.
Disable the fuel pump by disconnecting the inertia fuel shutoff switch.
Observe the incandescent test lamp while cranking the engine.

Is the test lamp blinking consistently?

Yes	No
KEY OFF. GO to JF3.	KEY OFF. GO to JF4.

JF3 CHECK THE FUNCTIONALITY OF THE SUSPECT COIL

Carry out a visual inspection. Closely inspect the coil case and boot for carbon tracking, cracks and torn or improperly installed boots.
Remove the suspect coil (as determined from the table) from the spark plug.
Connect air gap spark tester 303-D037 (D81P-6666-A) or equivalent to the suspect coil.
If WDS or an equivalent tester is available, use the scope function to verify the problem.
Suspect Coil connector connected.
Observe the spark tester while cranking the engine.

Is a bluish-white spark present?

Yes	No
KEY OFF. INSPECT the spark plug, REPLACE if necessary. GO to PINPOINT TEST Z step 1 .	KEY OFF. INSTALL a new Suspect Coil. INSPECT the spark plug, REPLACE if necessary. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .

JF4 CHECK IGN START/RUN VOLTAGE TO SUSPECT COIL

Key ON Engine OFF.
Suspect Coil connector disconnected.
Measure the voltage between:

( + )COP Connector, Harness Side	( - )Vehicle battery
COP	Negative terminal

Is the voltage greater than 10 V?

Yes	No
KEY OFF. GO to JF6.	KEY OFF. GO to JF5.

JF5 DETERMINE THE VEHICLE BEING DIAGNOSED

Are you servicing an LS6, LS8 or Thunderbird?

Yes	No
GO to PINPOINT TEST B step 5 .	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 Repair Verification Drive Cycle. REFER to DIAGNOSTIC METHODS - CNG, FLEX-FUEL & GASOLINE , Drive Cycle.

JF6 CHECK THE SUSPECT COIL DRIVER (CD) CIRCUIT FOR AN OPEN IN THE HARNESS

PCM connector disconnected.
Suspect Coil connector disconnected.
Measure the resistance between:

( + )PCM Connector, Harness Side	( - )COP Connector, Harness Side
Suspect coil driver.	COP

Is the resistance less than 5 ohms?

Yes	No
GO to JF7.	REPAIR open circuit. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .

JF7 CHECK THE SUSPECT COIL DRIVER (CD) CIRCUIT FOR A SHORT TO VPWR IN THE HARNESS

Key ON Engine OFF.
Measure the voltage between:

( + )PCM Connector, Harness Side	( - )Vehicle battery
Suspect coil driver.	Negative terminal

Is the voltage less than 1 V?

Yes	No
KEY OFF. GO to JF8.	KEY OFF. REPAIR short circuit to PWR. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .

JF8 CHECK THE SUSPECT COIL DRIVER (CD) CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Disconnect the scan tool.
Measure the resistance between:

( + )PCM Connector, Harness Side	( - )Vehicle battery
Suspect coil driver.	Negative terminal

Is the resistance greater than 10K ohms?

Yes	No
INSTALL a new PCM and retest vehicle. REFER to , FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM If the concern or DTC is still present, GO to JF9 to check for damaged coil, otherwise COMPLETE Misfire Monitor Repair Verification Drive Cycle. Refer to DRIVE CYCLES .	REPAIR short circuit to GND. If symptom or DTC is still present, GO to JF9 to check for damaged coil, otherwise COMPLETE Misfire Monitor Repair Verification Drive Cycle Refer to DRIVE CYCLES .

JF9 CHECK THE SUSPECT COIL FOR DAMAGE

Remove the suspect coil (as determined from the table) from the spark plug.
Connect air gap spark tester 303-D037 (D81P-6666-A) or equivalent to the suspect coil.
Locate and activate the fuel inertia switch to disable fuel pump.
Observe the spark tester while cranking the engine.

Is a bluish-white spark present?

Yes	No
KEY OFF. INSPECT the spark plug, REPLACE if necessary. GO to PINPOINT TEST Z step 1 .	KEY OFF. INSTALL a new COP.