Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2001 Mercury Sable, 2001 Mercury Mountaineer, 2001 Mercury Grand Marquis, 2001 Mercury Cougar, and 2001 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
After each service or repair procedure has been completed, reconnect all components. Clear DTCs and perform DRIVE CYCLE PROCEDURES
under ADDITIONAL SYSTEM FUNCTIONS. Ensure MISFIRE & FUEL MONITOR PROCEDURES are performed to verify repair. After drive cycle is complete, repeat QUICK TEST
procedures to ensure all EEC-V systems are working properly and DTCs are no longer present.
Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:
- Ignition Coils
- Ignition Coil Harness
- Powertrain Control Module (PCM)
NOTE:
On all models with distributorless electronic ignition, manufacturer does not recommend checking ignition timing, as faulty readings are common and timing is not adjustable.
IGNITION COIL-TO-CYLINDER CORRELATION (COIL-ON-PLUG)
| Application & Cylinder No. | Ignition Coil | Coil Driver | PCM Terminal No. | DTC | |
|---|---|---|---|---|---|
| 3.0L | |||||
| Escape | |||||
| 1 | A | A | 26 | P0351 | |
| 4 | D | D | 1 | P0354 | |
| 2 | B | B | 52 | P0352 | |
| 5 | E | E | 27 | P0355 | |
| 3 | C | C | 78 | P0353 | |
| 6 | F | F | 53 | P0356 | |
| LS | |||||
| 1 | A | A | C-31 | P0351 | |
| 4 | D | B | C-12 | P0354 | |
| 2 | B | C | C-23 | P0352 | |
| 5 | E | D | C-22 | P0355 | |
| 3 | C | E | C-13 | P0353 | |
| 6 | F | F | C-30 | P0356 | |
| 8-Cylinder Engines | |||||
| LS | |||||
| 1 | A | A | C-31 | P0351 | |
| 5 | E | B | C-23 | P0355 | |
| 4 | D | C | C-13 | P0354 | |
| 2 | B | D | C-1 | P0352 | |
| 6 | F | E | C-12 | P0356 | |
| 3 | C | F | C-22 | P0353 | |
| 7 | G | G | C-30 | P0357 | |
| 8 | H | H | C-38 | P0358 | |
| All Others | |||||
| 1 | A | A | 26 | P0351 | |
| 3 | C | B | 52 | P0353 | |
| 7 | G | C | 78 | P0357 | |
| 2 | B | D | 104 | P0352 | |
| 6 | F | E | 1 | P0356 | |
| 5 | E | F | 27 | P0355 | |
| 4 | D | G | 53 | P0354 | |
| 8 | H | H | 79 | P0358 | |
| 10-Cylinder Engines | |||||
| 1 | A | A | 26 | P0351 | |
| 6 | F | B | 1 | P0356 | |
| 5 | E | C | 52 | P0355 | |
| 10 | J | D | 27 | P0360 | |
| 2 | B | E | 78 | P0352 | |
| 7 | G | F | 53 | P0357 | |
| 3 | C | G | 104 | P0353 | |
| 8 | H | H | 79 | P0358 | |
| 4 | D | I | 102 | P0354 | |
| 9 | I | J | 82 | P0359 | |
DTCs P0350-P0360 indicate PCM did not receive a valid IDM pulse signal from ignition module (integrated in PCM). Possible causes are:
- Open Or Shorted IGN START/RUN Circuit
- Coil Driver (CD) Circuit Open, Or Shorted To Ground Or VPWR
- Faulty Ignition Coil
- Faulty PCM
NOTE:
Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION table of fault code setting condition.
FAULT CODE SETTING CONDITION
| Fault Code | KOEO | 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 |
- 1) Determine Which Coil Is Not Firing
Perform TEST JB and use test results, or compare DTC to IGNITION COIL-TO-CYLINDER CORRELATION (COIL-ON-PLUG) table to help determine which coil is not firing. Record cylinder, coil and PCM harness connector terminal number and go to next step. - 2) Check Functionality Of Suspect Coil Driver (CD) Circuit
Disconnect suspect coil (determined from IGNITION COIL-TO-CYLINDER CORRELATION (COIL-ON-PLUG) table. Connect test light between coil-on-plug IGN START/RUN terminal and suspect CD circuit terminal. See Fig 1 and Fig 2 . Disconnect Inertia Fuel Shutoff (IFS) switch to disable fuel pump. Observe test light while cranking engine. If test light blinks consistently, turn ignition switch to OFF position and go to next step. If test light does not blink consistently, turn ignition switch to OFF position and go to step 4). - 3) Check Functionality Of Suspect Coil
Remove suspect coil from spark plug. Install Spark Tester (D81P-6666-A) to suspect coil. Reconnect coil harness connector. Observe spark tester while cranking engine. If spark is not present, replace coil. Inspect spark plug and replace as necessary. If spark is present, check spark plug. Replace as necessary and retest. If spark plug is okay, no fault is present at this time. Go to TEST Z, step 1) . - 4) Check IGN START/RUN Voltage To Suspect Coil
Turn ignition switch to ON position. Using a DVOM, measure voltage between suspect coil harness connector IGN START/RUN terminal and ground. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less on LS, go to TEST B, step 5) . If voltage is 10 volts or less on all other models, check condition of related fuses/fuse links. If fuses/fuse links are blown, check for short to ground in IGN START/RUN circuit. Repair as necessary. If fuse/fuse links are okay, repair open in IGN START/RUN circuit. - 5) Check Suspect CD Circuit For Open In Harness
Turn ignition switch to OFF position. Disconnect PCM connector(s). Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Using a DVOM, measure resistance of suspect CD circuit between PCM harness connector and appropriate coil-on-plug harness connector. See Fig 1 or Fig 2 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in CD circuit. - 6) Check Suspect CD Circuit For Short To VPWR In Harness
Turn ignition switch to ON position. Using a DVOM, measure voltage of suspect CD circuit between ground and appropriate PCM harness connector terminal. See IGNITION COIL-TO-CYLINDER CORRELATION (COIL-ON-PLUG) table. If voltage is less than one volt, go to next step. If voltage is one volt or more, repair CD circuit for short to VPWR. - 7) Check Suspect CD Circuit For Short To Ground In Harness
Turn ignition switch to OFF position. Disconnect scan tool from DLC. Using a DVOM, measure resistance of suspect CD circuit between ground and appropriate PCM harness connector terminal. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in CD circuit. If symptom still exists after repair is complete, go to step 9) to check for damaged coil. - 8) Perform Intermittent Test On Suspect CD Circuit Harness
Using a DVOM, measure resistance of CD circuit between PCM harness connector and coil-on-plug harness connector. See Fig 1 or Fig 2 . Observe DVOM for indication of fault while wiggling and bending suspect CD circuit. Start at coil-on-plug harness connector and work toward PCM harness connector. Fault will be indicated by sudden change in resistance. If a fault is indicated, isolate fault and repair as necessary. If no fault is indicated, replace PCM. If symptom or DTC still exist after repair is complete, go to step 9) to check for damaged coil. - 9) Check Suspect Coil For Damage
Remove suspect coil from spark plug. Install Spark Tester (D81P-6666-A) to suspect coil. Reconnect coil harness connector. Observe spark tester while cranking engine. If spark is not present, replace coil. Inspect spark plug and replace as necessary. If spark is present, check spark plug. Replace as necessary and retest. If spark plug is okay, no fault is present at this time. Go to TEST Z, step 1) .