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Engine Ignition: Diagnosis Jaguar S-type I рестайлинг

Ignition System 2 illustrations ~1328 words

Inspection and Verification

  1. Verify the customer concern.
  2. Visually inspect for obvious signs of electrical damage. Visual inspection table Electrical Fuses (100 Amp midifuse and fuse 38 of the front power distribution box) Glow plug control module (GPCM) Engine management control relay Wiring harness(es) Electrical connector(s) Glow plug(s) Engine control module (ECM)
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) and test the system for normal operation 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 any fault codes before proceeding to the diagnostic trouble code (DTC) index.

Symptom chart

SymptomPossible causeAction
Poor starting (extreme weather conditions)Glow plugs inoperative/inefficient Fuel temperature too lowCheck the glow plug harnesses at the glow plugs and at the connection to the main harness. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Check for DTCs indicating a control module or circuit fault. The fuel system recycles fuel until operating temperature is reached to reduce this possibility.
High cold-engine emissionsAfter-glow phase inoperativeCheck the glow plug harnesses at the glow plugs and at the connection to the main harness. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Check for DTCs indicating a control module or circuit fault. After-glow is designed to function at engine temperatures below 50° C (122° F), and below 2500 RPM.
High cold-engine noise, vibration or harshnessAfter-glow phase inoperativeCheck the glow plug harnesses at the glow plugs and at the connection to the main harness. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Check for DTCs indicating a control module or circuit fault. After-glow is designed to function at engine temperatures below 50° C (122° F), and below 2500 RPM.

DTC index

DTCDescriptionPossible sourceAction
P0380Glow plug control module (GPCM)The GPCM is driven, but the glow plugs are not poweredFor GPCM circuit tests, Refer to Pinpoint Test B .
P0382Glow plug control module (GPCM)The GPCM is not driven, but the glow plugs are poweredFor GPCM circuit tests, Refer to Pinpoint Test B .
P0383Glow plug control module (GPCM) circuit lowGPCM control circuit: short circuit to groundFor GPCM control circuit tests, Refer to Pinpoint Test A .
P0384Glow plug control module (GPCM) circuit highGPCM control circuit: short circuit to powerFor GPCM control circuit tests, Refer to Pinpoint Test A .
P0670Glow plug control module (GPCM) circuit openGPCM control circuit: high resistanceFor GPCM control circuit tests, Refer to Pinpoint Test A .

Pinpoint Test A: GLOW PLUG CONTROL MODULE (GPCM) CONTROL CIRCUIT

Pinpoint Test A

A1 CHECK THE GPCM CONTROL CIRCUIT FOR SHORT CIRCUIT TO GROUND
  1. click to open the image
  2. Glow plug control module (GPCM) connector, FH20 Circuit Pin Ground 01 Control from ECM 02 Power supply from FPDB 03 Logic monitor 05
  3. click to open the image
  4. Engine control module (ECM) connector, C98 Circuit Pin Glow plug control module signal G3 Logic monitor E3
  5. Key off.
  6. Disconnect the GPCM electrical connector, FH20.
  7. Measure the resistance between
  8. FH20, harness side Battery Pin 02 Negative terminal
Is the resistance greater than 10 Kohms?
YES Go to step 3 . → A3
NO Go to step 2 . → 2
A2 CHECK WHETHER THE SHORT CIRCUIT IS IN THE HARNESS OR THE ECM
  1. Disconnect the ECM connector, C98.
  2. Measure the resistance between
  3. FH20, harness side Battery Pin 02 Negative terminal
Is the resistance greater than 10 Kohms?
YES An intermittent fault may be present in the wiring harness. Visually check for chaffed wires or other physical damage to the harness.
NO REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear the DTC, test the system for normal operation.
A3 CHECK THE GPCM CONTROL CIRCUIT FOR SHORT CIRCUIT TO POWER
  1. Key off.
  2. Measure the resistance between
  3. FH20, harness side Battery Pin 02 Positive terminal
Is the resistance greater than 10 Kohms?
YES Go to step 5 . → A5
NO Go to step 4 . → 4
A4 CHECK WHETHER THE SHORT CIRCUIT IS IN THE HARNESS OR THE ECM
  1. Disconnect the ECM connector, C98.
  2. Measure the resistance between
  3. FH20, harness side Battery Pin 02 Positive terminal
Is the resistance greater than 10 Kohms?
YES An intermittent fault may be present in the wiring harness. Visually check for chaffed wires or other physical damage to the harness.
NO REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear the DTC, test the system for normal operation.
A5 CHECK THE GPCM CONTROL CIRCUIT FOR HIGH RESISTANCE
  1. Disconnect the ECM connector, C98.
  2. Measure the resistance between
  3. FH20, harness side C98, harness side Pin 02 Pin G3
Is the resistance less than 10 ohms?
YES An intermittent fault may be present in the wiring harness. Visually check for chaffed wires or other physical damage to the harness. Refer to the warranty policy and procedures manual if a module is suspect.
NO REPAIR the high resistance circuit. This circuit includes connector, PI41. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear the DTC, test the system for normal operation.

Pinpoint Test B: GLOW PLUG CONTROL MODULE (GPCM) OUTPUT

Pinpoint Test B

B1 CHECK THE PERMANENT POWER SUPPLY TO THE GPCM
  1. click to open the image
  2. Glow plug control module (GPCM) connector, GP04 Circuit Pin Cylinder 1 output Pin 01 Cylinder 2 output Pin 02 Cylinder 3 output Pin 03 Cylinder 4 output Pin 04 Cylinder 5 output Pin 05 Cylinder 6 output Pin 06
  3. click to open the image
  4. Right hand glow plug connector, GP01 Circuit Pin Cylinder 1 01 Cylinder 2 02 Cylinder 3 03
  5. click to open the image
  6. Left hand glow plug connector, GP02 Circuit Pin Cylinder 4 01 Cylinder 5 02 Cylinder 6 03
  7. Disconnect the glow plug module connector, FH23 (this is an eyelet).
  8. Measure the voltage between
  9. FH23, harness side Battery Pin 01 Negative terminal
Is the voltage greater than 10 volts?
YES Go to step 2 . → B2
NO REPAIR the permanent power supply circuit. This circuit includes the 100A midi fuse. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear any DTCs, test the system for normal operation.
B2 CHECK THE IGNITION POWER SUPPLY TO THE GPCM
  1. Disconnect the glow plug module connector, FH20.
  2. Key on, engine off.
B3 Is the voltage greater than 10 volts?
  1. Measure the voltage between
  2. FH20, harness side Battery Pin 03 Negative terminal
Is the voltage greater than 10 volts?
YES Go to step 4 . → B4
NO REPAIR the ignition power supply circuit. This circuit includes fuse 38 of the front power distribution box. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear any DTCs, test the system for normal operation.
B4 CHECK THE GROUND TO THE GPCM
  1. Key off.
  2. Measure the resistance between
  3. FH20, harness side Battery Pin 01 Negative terminal
Is the resistance less than 10 ohms?
YES Go to step 5 . → B5
NO REPAIR the high resistance circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear any DTCs, test the system for normal operation.
B5 CHECK THE GLOW PLUG OUTPUT CIRCUITS FOR SHORT CIRCUIT TO GROUND
  1. Key off.
  2. Disconnect the glow plug module connector, GP04
  3. Disconnect the glow plug connectors, GP01 and GP02.
  4. Measure the resistance between
  5. Right hand bank GP01, harness side Battery Pin 01 Negative terminal Pin 02 Pin 03
  6. Left hand bank GP02, harness side Battery Pin 04 Negative terminal Pin 05 Pin 06
Is the resistance greater than 100 Kohms?
YES Go to step 6 . → B6
NO REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear any DTCs, test the system for normal operation.
B6 CHECK THE GLOW PLUG OUTPUT CIRCUITS FOR SHORT CIRCUIT TO POWER
  1. Measure the resistance between
  2. Right hand bank GP01, harness side Battery Pin 01 Positive terminal Pin 02 Pin 03
  3. Left hand bank GP02, harness side Battery Pin 04 Positive terminal Pin 05 Pin 06
Is the resistance greater than 100 Kohms?
YES Go to step 7 . → B7
NO REPAIR the short circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear any DTCs, test the system for normal operation.
B7 CHECK THE GLOW PLUG OUTPUT CIRCUITS FOR HIGH RESISTANCE
  1. Measure the resistance between
  2. Right hand bank GP04, harness side GP01, harness side Pin 01 Pin 01 Pin 02 Pin 02 Pin 03 Pin 03
  3. Left hand bank GP04, harness side GP02, harness side Pin 04 Pin 01 Pin 05 Pin 02 Pin 06 Pin 03
Is the resistance less than 10 ohms?
YES If DTCs P0380 or P0382 are logged and the tests above have not identified a circuit fault, a control module may be at fault.
NO REPAIR the high resistance circuit. For additional information, See appropriate SYSTEM WIRING DIAGRAMS article. Clear the DTC, test the system for normal operation.

Scheme 14

Scheme 14: Removal
Scheme 14: Removal

Scheme 15

Scheme 15
Scheme 15
  1. Remove the intake air shutoff throttle. Refer to «Intake Air Shutoff Throttle»(ref-311272-S15018844262009032500000) article.
  2. Detach the glow plug rail.
  3. Remove the glow plugs.

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