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Engine Ignition (4.2L): Diagnosis Jaguar S-type I рестайлинг

Ignition System 4 illustrations ~2038 words

Engine Ignition - Diagnostic Procedures

  1. Verify the customer concern by operating the system.
  2. Visually inspect for obvious signs of mechanical or electrical damage.
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. If the concern is not visually evident, refer to «Symptom Chart»(ref-311312-S22075159812009032500000) .
ConditionPossible SourceAction
DTC P0300 Random multiple cylinder misfire detected. DTC P0301 to P0308: Misfire at cylinders 1 to 8Poor cylinder compression. Damaged or worn piston rings. Inlet/exhaust valve stuck open/closed. Worn camshaft. Damaged cylinder head gasket. Spark plug fouled/incorrect gap.Refer to Engine article.
Fuel delivery pressure high/low. Faulty injector (inoperative/leaking). Fuel injector continuously open. Fuel contamination. Fuel injector circuit fault.Refer to Fuel Charging and Controls article.
Damaged ignition coil. Damaged electrical harness/connection. Damaged spark plug.Refer to Symptom Chart .

Related Faults/Codes

ConditionPossible SourceAction
DTC P0351, P0353, P0355, P0357: Ignition coils 1A, 2A, 3A or 4A primary circuit malfunctions.Ignition coil open/short circuit. Ignition coil insulation breakdown. Damaged harness. Connector pins bent or corroded. Damaged ignition circuit ground. Damaged engine control module (ECM).GO to "Pinpoint Test A" for individual DTC.
DTC P0352, P0354, P0356, P0358: Ignition coils 1B, 2B, 3B or 4B primary circuit malfunctions.Ignition coil open/short circuit. Ignition coil insulation breakdown. Damaged harness. Connector pins bent or corroded. Damaged ignition circuit ground fault. Damaged ECM.GO to "Pinpoint Test A" for individual DTC.
DTC P1367: All right-hand bank ignition coils, primary circuit malfunctions (1A, 2A, 3A, 4A).Ignition coil open/short circuit. Ignition coil insulation breakdown. Damaged harness. Connector pins bent or corroded. Damaged ignition circuit ground. Damaged ECM.GO to "Pinpoint Test A" for individual DTC.
DTC P1368: All left-hand bank ignition coils, primary circuit malfunctions (1B, 2B, 3B, 4B).Ignition coil open/short circuit. Ignition coil insulation breakdown. Damaged harness. Connector pins bent or corroded. Damaged ignition circuit ground fault. Damaged ECM.GO to "Pinpoint Test A" for individual DTC.

Symptom Chart

Scheme 9

Scheme 9
Scheme 9
Pin NumberCircuit FunctionCircuit Color
611B ignition coil triggerGreen/White
622B ignition coil triggerGreen/White
633B ignition coil triggerGreen/Red
644B ignition coil triggerYellow/Red
871A ignition coil triggerGreen/Blue
882A ignition coil triggerYellow
893A ignition coil triggerYellow/Red
904A ignition coil triggerGreen/Red

Powertrain Control Module Harness Electrical Connector

Scheme 10

Scheme 10
Scheme 10
Pin NumberCircuit FunctionCircuit Color
1Ignition coil voltage supplyRed/White
2Ignition coil diagnostic signal1A and 4A - Green/Black. 2A and 3A - Yellow/Black
3Ignition coil ground supplyBlack
4Ignition coil trigger1A - Green/Blue, 2A - Yellow, 3A - Yellow/Red, 4A - Green/Red

1A, 2A, 3A, 4A Ignition Coil Harness Electrical Connectors

Pin NumberCircuit FunctionCircuit Color
1Ignition coil voltage supplyRed/White
2Ignition coil diagnostic signal1B and 4B - Yellow/Black. 2B and 3B - Green/Black
3Ignition coil ground supplyBlack
4Ignition coil trigger1B and 2B - Green/White, 3B - Green/Red, 4B - Yellow/Red

1B, 2B, 3B, 4B Ignition Coil Harness Electrical Connectors

Scheme 11

Scheme 11
Scheme 11
Pin NumberCircuit Function
1Ignition coil voltage supply
2Ignition coil diagnostic signal
3Ignition coil ground supply
4Ignition coil trigger

1A, 2A, 3A, 4A, 1B, 2B, 3B, 4B Ignition Coils

Pinpoint Test A: Ignition Coils - P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, P1367, P1368

Note. Unless multiple cylinder misfires are apparent, only one circuit will normally need to be tested. The DTC set will indicate which cylinder is misfiring.

Pinpoint Test A

A1 CHECK COIL FUNCTION BY SUBSTITUTION
  1. Replace the suspected faulty coil with a good one.
  2. CLEAR the DTC. TEST the system for normal operation.
  3. Does the same DTC reoccur? The DTC will indicate if the same cylinder is misfiring.
YES Go to step 2 . → A2
NO CLEAR the DTC. TEST the system for normal operation.
A2 CHECK THE IGNITION COIL SUPPLY VOLTAGE CIRCUIT
  1. Disconnect the relevant right-hand bank ignition coil electrical connector(s).
  2. Turn the ignition switch to the ON position.
  3. Measure the voltage between
  4. Disconnect the relevant left-hand bank ignition coil electrical connector(s).
  5. Measure the voltage between
Is the voltage greater than 10.5 Volts?
YES Go to step 3 . → A3
NO REPAIR the relevant ignition coil supply voltage circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs. TEST the system for normal operation.
A3 CHECK THE IGNITION COIL GROUND CIRCUIT
  1. Switch the ignition to the OFF position.
  2. Disconnect the relevant right-hand bank ignition coil electrical connector(s).
  3. Measure the resistance between
  4. Disconnect the relevant left-hand bank ignition coil electrical connector(s).
  5. Measure the resistance between
Is the resistance less than 5 ohms?
YES Go to step 4 . → A4
NO REPAIR the relevant ignition coil ground circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs. TEST the system for normal operation.
A4 CHECK THE CONTINUITY OF THE IGNITION COIL TRIGGER SUPPLY CIRCUIT
  1. Disconnect the ECM electrical connector PI001.
  2. Check the continuity of the ignition coil trigger supply circuit between the relevant ignition coil electrical connector(s) and the ECM electrical connector
Is the resistance less than 5 ohms?
YES Go to step 5 . → A5
NO REPAIR the ignition coil trigger supply circuit between the relevant ignition coil electrical connector(s) and the ECM electrical connector. CLEAR the DTCs. TEST the system for normal operation.
A5 CHECK THE CONTINUITY BETWEEN THE IGNITION COIL AND THE ECM
  1. Check the continuity of the ignition coil diagnostic signal circuit, between the ignition coil electrical connector(s) and the ECM electrical connector
Is the resistance less than 5 Ohms?
YES INSTALL a new ECM. For additional information, refer to «Electronic Engine Controls»(ref-311294) article. Before replacing a ECM, contact Dealer technical support. CLEAR the DTCs. TEST the system for normal operation.
NO REPAIR the circuit between the ignition coil electrical connector(s) and the ECM electrical connector. CLEAR the DTCs. TEST the system for normal operation.

Inspection and Verification

  1. Verify the customer concern.
  2. Visually inspect for obvious signs of mechanical or electrical damage. Visual inspection Mechanical Electrical Engine oil level Cooling system coolant level Fuel level Fuel contamination/grade/quality Fuses Wiring harness Loose or corroded electrical connectors Ignition coils Sensor(s) Engine control module (ECM) Transmission control module (TCM)
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. If the cause is not visually evident use the Jaguar approved diagnostic system or a scan tool to retrieve the fault codes before proceeding to the diagnostic trouble code (DTC) Index.

Symptom Chart

SymptomPossible sourceAction
Engine cranks, but does not fireEngine breather system disconnected/restricted Ignition system Fuel system Harness Crankshaft position (CKP) sensor ECM faultCheck the engine breather system, Refer to Engine Emission Control - VIN Range: N52207->N99999 article. For ignition system tests, Refer to Pinpoint Test A . Check the fuel pressure, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For CKP tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. Refer to the warranty policy and procedures manual if an ECM is suspect.
Engine cranks and fires, but will not startEvaporative emissions purge valve Fuel pump Spark plugs HT short to ground (tracking) check rubber boots for cracks/damage Ignition coil failure(s) HarnessFor purge valve tests, Refer to Evaporative Emissions - VIN Range: N52207->N99999 article. Check the fuel pressure, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For spark plug tests, Refer to Pinpoint Test B . For ignition coil circuit tests, Refer to Pinpoint Test A .
Difficult to start coldCoolant anti-freeze content Battery CKP sensor Exhaust gas recirculation (EGR) valve stuck open Fuel pump Purge valveCheck the anti-freeze content. For battery information, Refer to Battery article. For CKP sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For EGR valve tests, and Refer to Engine Emission Control - VIN Range: N52207->N99999 article. Check the fuel pressure, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For purge valve tests, and Refer to Evaporative Emissions - VIN Range: N52207->N99999 article.
Difficult to start hotInjector leak Engine fuel temperature (EFT) sensor Intake air temperature (IAT) sensor Mass air flow (MAF) sensor Purge valve Fuel pump Ignition system EGR valve stuck openFor fuel injectors, Refer to Fuel Injectors article. For EFT, IAT and MAF sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For purge valve tests, and Refer to Evaporative Emissions - VIN Range: N52207->N99999 article. Check the fuel pressure, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For ignition coil circuit tests, Refer to Pinpoint Test A . For EGR valve tests, and Refer to Engine Emission Control - VIN Range: N52207->N99999 article.
Difficult to start after hot soak (vehicle standing after engine has reached operating temperature)Injector leak EFT sensor IAT sensor MAF sensor Purge valve Fuel pump Ignition system EGR valve stuck openFor fuel injectors, Refer to Fuel Injectors article. For EFT, IAT and MAF sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For purge valve tests, and Refer to Evaporative Emissions - VIN Range: N52207->N99999 article. Check the fuel pressure, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For ignition coil circuit tests, Refer to Pinpoint Test A . For EGR valve tests, and Refer to Engine Emission Control - VIN Range: N52207->N99999 article.
Engine stalls soon after startBreather system disconnected/restricted ECM relay Harness MAF sensor Ignition system Air filter restricted Fuel lines FRP sensor Air leakageFor breather system, Refer to Engine Emission Control - VIN Range: N52207->N99999 article. For ECM relay and MAF sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For ignition coil circuit tests, Refer to Pinpoint Test A . For air filter information, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article. Check the fuel lines, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For FRP sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For intake system information, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article.
Engine hesitates/poor accelerationFuel pump Injector leak Fuel pressure Fuel lines Air leakage Throttle position (TP) sensors Throttle motor Ignition system EGR valve stuck open HO2 sensors Transmission malfunction Restricted pedal travel (carpet, etc) Accelerator pedal position (APP) sensorCheck the fuel pressure, check the fuel lines, Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For intake system, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article. For TP sensor and throttle motor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For ignition coil circuit tests, Refer to Pinpoint Test A . For EGR valve tests, and Refer to Engine Emission Control - VIN Range: N52207->N99999 article. Check for DTCs relating to HO2 sensors. Refer to DTC Index for pinpoint tests for DTC set. For transmission information, and Refer to Diagnostic Strategy - VIN Range: N52207->N99999 article. Check the accelerator pedal travel. For APP sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article.
Engine backfiresFuel pump Fuel lines Air leakage MAF sensor HO2 sensors Ignition system Sticking variable camshaft timing (VCT) hub APP sensorCheck the fuel pressure, check the fuel lines, Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For intake system, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article. For MAF sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. Check for DTCs relating to HO2 sensors. Refer to DTC Index for pinpoint tests for DTC set. For ignition coil circuit tests, Refer to Pinpoint Test A . For VCT information, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For APP sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article.
Engine surgesFuel pump Fuel lines MAF sensor Harness TP sensors Throttle motor Ignition systemCheck the fuel pressure, check the fuel lines, Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For MAF, TP sensor and throttle motor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For ignition coil circuit tests, Refer to Pinpoint Test A .
Engine detonates/knocksKnock sensor (KS) circuit malfunction Fuel pump Fuel lines FRP sensor MAF sensor HO2 sensors Air leakage Sticking VCT hub BARO sensor malfunction (internal ECM fault)For KS circuit tests, Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. Check the fuel pressure, check the fuel lines, and Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For FRP, MAF and HO2 sensor tests, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For intake system, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article. Check DTCs for VCT range/performance fault. For VCT information, and Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. Refer to the warranty policy and procedures manual if an ECM is suspect.
No throttle responseAPP sensor malfunction TP sensors Throttle motorFor APP, TP sensor and throttle motor tests, Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article.
Poor throttle responseAPP sensor malfunction TP sensors ECT sensor MAF sensor Transmission malfunction Traction control event Air leakage Breather system disconnected/restrictedFor APP, TP, ECT and MAF sensor tests, Refer to Electronic Engine Controls - VIN Range: N52207->N99999 article. For transmission information, and Refer to Diagnostic Strategy - VIN Range: N52207->N99999 article. For intake system, and Refer to Intake Air Distribution and Filtering - VIN Range: N52207->N99999 article. For breather system information, and Refer to Engine Emission Control - VIN Range: N52207->N99999 article.

DTC Index

Note. Generic scan tools may not read the codes listed, or may read only 5-digit codes. Match the 5 digits from the scan tool to the first 5 digits of the 7-digit code listed to identify the fault (the last 2 digits give extra information read by the manufacturer-approved diagnostic system).

DTCDescriptionPossible causesAction
P035100Cylinder 1 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035200Cylinder 2 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035300Cylinder 3 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035400Cylinder 4 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035500Cylinder 5 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035600Cylinder 6 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035700Cylinder 7 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P035800Cylinder 8 ignition coil primary/secondary circuitECM to ignition module/coil drive circuit: short circuit to ground, high resistance Ignition module/coil ground circuit: high resistance Ignition module/coil supply circuit: open circuit (including relay)For ignition coil tests, Refer to Pinpoint Test A .
P131500Persistent misfireSpark plug failure/fouled/incorrect gap Ignition coil failure ECM to ignition coil primary circuit fault (cylinder misfire detected DTC also flagged) Fuel delivery pressure low Fuel injector circuit fault(s) (injector DTCs also flagged) Cylinder compression lowFor spark plug tests, Refer to Pinpoint Test B . For ignition coil circuit tests, Refer to Pinpoint Test A . Check the fuel pressure, Refer to Fuel Tank and Lines - 2.5L/3.0L/4.2L, VIN Range: N52207->N99999 article. For injector circuit tests, and Refer to Fuel Charging and Controls - VIN Range: N52207->N99999 article. Check the cylinder compressions, and Refer to Engine article.
P136700Ignition amplifier group AIgnition monitoring circuit to ECM: open circuit, short circuit to ground, short circuit to power Ignition module/coils right hand bank ground circuit faultFor ignition coil tests, Refer to Pinpoint Test A .
P136800Ignition amplifier group BIgnition monitoring circuit to ECM: open circuit, short circuit to ground, short circuit to power Ignition module/coils left hand bank ground circuit faultFor ignition coil tests, Refer to Pinpoint Test A .

Pinpoint Test A: IGNITION COIL CIRCUITS

Note. Unless multiple cylinder misfires are apparent, only one circuit will normally need to be tested. The DTC set will indicate which cylinder is misfiring.

Pinpoint Test A

A1 CHECK THE IGNITION COIL SUPPLY VOLTAGE CIRCUIT
  1. Disconnect the relevant ignition coil electrical connector
  2. Ignition coil connector Cylinder 1, PI02 Cylinder 2, PI06 Cylinder 3, PI03 Cylinder 4, PI07 Cylinder 5, PI04 Cylinder 6, PI08 Cylinder 7, PI05 Cylinder 8, PI09
  3. Key on, engine off.
  4. Make sure the ignition relay is energized.
  5. Measure the voltage between
  6. Ignition coil connector, harness side Battery Pin 01 Negative terminal
Is the voltage less than 10.5 Volts?
YES REPAIR the relevant ignition coil supply circuit. This circuit includes fuse 30 of the front power distribution box and the ignition relay. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 2 . → 2
A2 CHECK THE IGNITION COIL SWITCHING CIRCUITS FOR SHORT CIRCUIT TO GROUND
  1. Key off.
  2. Measure the resistance between
  3. Ignition coil connector, harness side Battery Pin 04 Negative terminal
Is the resistance less than 10,000 ohms?
YES REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 3 . → 3
A3 CHECK THE IGNITION COIL SWITCHING CIRCUITS FOR SHORT CIRCUIT TO POWER
  1. Measure the resistance between
  2. Ignition coil connector, harness side Battery Pin 04 Positive terminal
Is the resistance less than 10,000 ohms?
YES REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 4 . → 4
A4 CHECK THE IGNITION COIL MONITOR CIRCUITS FOR SHORT CIRCUIT TO GROUND
  1. Measure the resistance between
  2. Ignition coil connector, harness side Battery Pin 02 Negative terminal
Is the resistance less than 10,000 ohms?
YES REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 5 . → 5
A5 CHECK THE IGNITION COIL MONITOR CIRCUITS FOR SHORT CIRCUIT TO POWER
  1. Measure the resistance between
  2. Ignition coil connector, harness side Battery Pin 02 Positive terminal
Is the resistance less than 10,000 ohms?
YES REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 6 . → 6
A6 CHECK THE IGNITION COIL GROUND CIRCUIT FOR HIGH RESISTANCE
  1. NOTE: Unless multiple cylinder misfires are apparent, only one circuit will normally need to be tested. The DTC set will indicate which cylinder is misfiring.
  2. Measure the resistance between
  3. Cylinder 1 ignition coil connector, harness side Battery PI02, pin 03 Negative terminal
  4. Cylinder 2 ignition coil connector, harness side Battery PI06, pin 03 Negative terminal
  5. Cylinder 3 ignition coil connector, harness side Battery PI03, pin 03 Negative terminal
  6. Cylinder 4 ignition coil connector, harness side Battery PI07, pin 03 Negative terminal
  7. Cylinder 5 ignition coil connector, harness side Battery PI04, pin 03 Negative terminal
  8. Cylinder 6 ignition coil connector, harness side Battery PI08, pin 03 Negative terminal
  9. Cylinder 7 ignition coil connector, harness side Battery PI05, pin 03 Negative terminal
  10. Cylinder 8 ignition coil connector, harness side Battery PI09, pin 03 Negative terminal
Is the resistance greater than 5 ohms?
YES REPAIR the high resistance circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 7 . → 7
A7 CHECK THE IGNITION COIL SWITCHING CIRCUITS FOR HIGH RESISTANCE
  1. NOTE: Unless multiple cylinder misfires are apparent, only one circuit will normally need to be tested. The DTC set will indicate which cylinder is misfiring.
  2. Disconnect the ECM electrical connector, PI300.
  3. Measure the resistance between
  4. Cylinder 1 ignition coil connector, harness side ECM connector PI300, harness side PI02, pin 04 Pin 61
  5. Cylinder 2 ignition coil connector, harness side ECM connector PI300, harness side PI06, pin 04 Pin 60
  6. Cylinder 3 ignition coil connector, harness side ECM connector PI300, harness side PI03, pin 04 Pin 59
  7. Cylinder 4 ignition coil connector, harness side ECM connector PI300, harness side PI07, pin 04 Pin 58
  8. Cylinder 5 ignition coil connector, harness side ECM connector PI300, harness side PI04, pin 04 Pin 57
  9. Cylinder 6 ignition coil connector, harness side ECM connector PI300, harness side PI08, pin 04 Pin 56
  10. Cylinder 7 ignition coil connector, harness side ECM connector PI300, harness side PI05, pin 04 Pin 55
  11. Cylinder 8 ignition coil connector, harness side ECM connector PI300, harness side PI09, pin 04 Pin 54
Is the resistance greater than 5 ohms?
YES REPAIR the high resistance circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO Go to step 8 . → 8
A8 CHECK THE IGNITION COIL MONITOR CIRCUITS FOR HIGH RESISTANCE
  1. NOTE: Unless multiple cylinder misfires are apparent, only one circuit will normally need to be tested. The DTC set will indicate which cylinder is misfiring.
  2. Measure the resistance between
  3. Cylinder 1 ignition coil connector, harness side ECM connector PI300, harness side PI02, pin 02 Pin 62
  4. Cylinder 2 ignition coil connector, harness side ECM connector PI300, harness side PI06, pin 02 Pin 64
  5. Cylinder 3 ignition coil connector, harness side ECM connector PI300, harness side PI03, pin 02 Pin 64
  6. Cylinder 4 ignition coil connector, harness side ECM connector PI300, harness side PI07, pin 02 Pin 62
  7. Cylinder 5 ignition coil connector, harness side ECM connector PI300, harness side PI04, pin 02 Pin 64
  8. Cylinder 6 ignition coil connector, harness side ECM connector PI300, harness side PI08, pin 02 Pin 62
  9. Cylinder 7 ignition coil connector, harness side ECM connector PI300, harness side PI05, pin 02 Pin 62
  10. Cylinder 8 ignition coil connector, harness side ECM connector PI300, harness side PI09, pin 02 Pin 64
Is the resistance greater than 5 ohms?
YES REPAIR the high resistance circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. CLEAR the DTCs and test the system for normal operation.
NO INSTALL a new ignition coil to the relevant cylinder. See «Ignition Coil-On-Plug»(ref-311312-S17589001482009032500000) . Clear the DTC and test the system for normal operation. Refer to the warranty policy and procedures manual if an ECM is suspect.

Pinpoint Test B: CHECK SPARK PLUG RESISTANCE

Note. Only resisted spark plugs must be used.

Pinpoint Test B

B1 CHECK SPARK PLUG RESISTANCE
  1. Remove the suspect spark plug(s).
  2. Measure the resistance between
  3. Spark plug Spark plug Center electrode tip HT contact
  4. Is the resistance between 8,000 and 12,000 ohms? (nominal 10,000 ohms)
YES Check ignition coil and circuits. See possible sources list for misfire.
NO INSTALL a new spark plug. CLEAR the DTC. TEST the system for normal operation.

Scheme 12

Scheme 12: Removal
Scheme 12: Removal
  1. Remove the oil level indicator.
  2. Remove the ignition coil-on-plug cover.
  3. Disconnect the ignition coil-on-plug electrical connector.
  4. Disconnect the brake servo pressure sensor electrical connector.
  5. Remove the ignition coil-on-plug. Remove the retaining bolt.

More articles — Engine Ignition (4.2L)