Jaguar X-Type Sedan and Estate (Wagon). Manual - part 303
Published: 11-May-2011
Glow Plug System - Glow Plug System
Diagnosis and Testing
Principle of operation
As common rail diesel engines have better cold-starting characteristics than traditional diesel engines, the glow plugs have two functions on
this engine:
Pre-heat stage
In this stage, the glow plugs function as normal, preheating the combustion chambers to aid cold starting.
After-glow stage
At engine speeds below 2,500 rpm, and at temperatures below 50 degrees C (122 degrees F), the glow plugs continue to heat the cylinders
to improve idling and reduce emissions.
Warning light
The glow plug warning light on this vehicle not only informs the driver that the glow plugs are operating, but also as a malfunction indicator
lamp (MIL) for the engine management system. For additional information,
REFER to:
Glow Plug System
(303-07B Glow Plug System, Description and Operation).
Inspection and Verification
1. Verify the customer concern.
1.
2. Visually inspect for obvious signs of electrical damage.
2.
Electrical
Fuse 22, front power distribution box (60 Amp)
Fuse 18, front power distribution box (10 Amp)
Glow plug relay (R10, front power distribution box)
Engine management control relay (R7, front power distribution box)
W iring harness
Electrical connector(s)
Glow plug(s)
Engine control module (ECM)
CAUTION: W hen probing connectors to take measurements in the course of the pinpoint tests, use the adaptor kit, part number
3548-1358-00. Failure to follow this instruction may result in damage to the vehicle.
• NOTE: This section contains references to Parameter Identifiers (PIDs). Where the Jaguar approved diagnostic system is not available, a
scan tool may be used to access these PIDs, all of which give information, and some of which can be used to both read information and to
activate components. The format of the information may vary, depending on the tool used.
• NOTE: As well as carrying out its normal function the glow plug indicator also acts as an engine check lamp which will flash continuously
when a hard diagnostic trouble code (DTC) is detected by the ECM. Soft DTCs are also stored by the ECM but will only be identified if the
system is checked for DTCs using the Jaguar approved diagnostic system or a scan tool.
• NOTE: If a DTC is detected, all DTCs must be cleared after the concern is repaired. Failure to clear all DTCs may cause driveability
concerns.
• NOTE: When performing voltage or resistance tests, always use a digital multimeter (DMM) accurate to 3 decimal places, and with an
up-to-date calibration certificate. W hen testing resistance, always take the resistance of the DMM leads into account.
• NOTE: Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.
• NOTE: If DTCs are recorded and the symptom is not present when performing the pinpoint tests, an intermittent concern may be the
cause. Always check for loose connections and corroded terminals.
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next
step.
3.
Diagnostic trouble code (DTC) index
DTC
Condition
Possible source
Action
P0380 Glow plug heater
circuit
Glow plug heater circuit: relay driver open circuit, short
circuit
For glow plug circuit tests, GO to Pinpoint
Test
A.
Pinpoint Tests
PINPOINT TEST A : GLOW PLUG CIRCUIT TESTS
TEST CONDITIONS
DETAILS/RESULTS/ACTIONS
A1: CHECK THE GLOW PLUG CIRCUIT(S) FOR SHORT CIRCUIT TO POWER