Diagnostics and checks of electronic controls (Defender 2007+)

Inspection and verification

1. Check the customer's complaint.

2. Visually inspect for obvious mechanical and electrical problems.

Visual check

Mechanical elements	electrical equipment
• Engine oil level • Coolant level • Fuel level / contamination • Fuel leaks • injection pump • Air intake system • Drive belt • Attachment / condition of the sensor • Engine cooling fan	• Fuses • Fuse P110 • Fuse 41, engine room electrical box • Wiring harness • Electrical plug (s) • Nozzles • Glow plugs • Sensor power supply 5 V • Sensor (And) • The engine control unit (ECM)

3. If there is an obvious reason for the problem you identified or described by the client, eliminate it before proceeding to further actions (if possible).

4. Before Referring to the Symptom Table or DTC Index (DTC) read all DTCs with a validated diagnostic system or scan tool.

• Clear all DTCs after troubleshooting.

Symptom table

sign	Possible reasons	Operation
Engine crankshaft does not turn	Starter relay output circuit high resistance Starter relay output circuit short circuit to +battery Starter malfunction Ignition Switch Malfunction CAN bus failure (Control Area Network)	Check starter relay and circuits. Refer to electrical manuals. Check the operation of the ignition switch. Check for DTCs (DTC), indicating a fault in the CAN network.
The crankshaft turns, but the engine does not start	Inertial fuel shutoff sensor (IFS) Malfunction of the relay of the block of management of the engine (ECM) Low/contaminated fuel Air leak Malfunction in the low pressure fuel system Clogged fuel filter Suction control valve failure High pressure fuel pump malfunction crankshaft position sensor (CKP)	Check if the inertial switch is activated. Check ECM main relay and circuits. Refer to the electrical manual. Check the level and condition of the fuel. Drain approximately 1 liter of fuel and let it sit for 1 minute. Check that there is no separation indicating the presence of water or other liquid in the fuel. Check air intake system for leaks. Check the low pressure fuel system for leaks/damage. Check the fuel filter, check for DTCs indicating a malfunction of the injection pump. Check high pressure fuel pump: For more information refer to: Fuel pump (303-04A Fuel supply and controls - Diesel engine ID4 2.4L, Removal and installation). Check the CKP sensor circuits. Refer to electrical manuals. Install a new crankshaft position sensor if necessary (TFR). For more information refer to: Crankshaft Position Sensor (TFR) (303-14 Electronic controls - Diesel engine ID4 2.4L, Removal and installation).
Difficult start	Glow plug system malfunction (very cold conditions) Low/contaminated fuel Air leak Malfunction in the low pressure fuel system Clogged fuel filter Suction control valve failure EGR valve malfunction (EGR)	NOTE: Make sure the latest throttle inlet EGR valve is installed. Using the manufacturer approved diagnostic system, check and install the latest software on the engine control unit. Check the glow plug circuits. Refer to electrical manuals. Check fuel level/condition. Drain approximately 1 liter of fuel and let it sit for 1 minute. Check that there is no separation indicating the presence of water or other liquid in the fuel. Check air intake system for leaks. Check the low pressure fuel system for leaks/damage. Check the fuel filter, check for DTCs indicating a malfunction of the injection pump. EGR valve checks: For more information, see: Emission Control (303-08 Emission Control - ID4 2.4L Diesel Engine, Diagnostics and Checks).
Uneven idle operation	Air intake system malfunction Low/contaminated fuel Malfunction in the low pressure fuel system Clogged fuel filter Suction control valve failure EGR valve malfunction (EGR)	NOTE: Make sure the latest throttle inlet EGR valve is installed. Using the manufacturer's approved diagnostic system, check and install the latest software on the engine control unit. Check the air intake system for leaks. Check fuel level/condition. Drain approximately 1 liter of fuel and let it sit for 1 minute. Check that there is no separation indicating the presence of water or other liquid in the fuel. Check the low pressure fuel system for leaks/damage. Check the fuel filter, check for DTCs indicating a malfunction of the injection pump. EGR valve checks: For more information, see: Emission Control (303-08 Emission Control - ID4 2.4L Diesel Engine, Diagnostics and Checks).
Lack of power during acceleration	Air intake system malfunction Clogged exhaust system Low fuel pressure EGR valve malfunction (EGR) Turbocharger Actuator Malfunction	NOTE: Make sure the latest throttle inlet EGR valve is installed. Using the manufacturer approved diagnostic system, check and update the engine control unit with the latest software version. Check the air intake system for leaks or blockages. Check for blockage/clogging in the exhaust system, install new elements if necessary. For more information refer to: Catalytic Converter (309-00 Exhaust system -Diesel engine ID4 2.4L, Removal and installation). Check for diagnostic trouble codes (DTC), indicating incorrect fuel pressure. For EGR valve checks: For more information, refer to: Emission Control (303-08 Emission Control -ID4 2.4L Diesel Engine, Diagnostics and Checks). Check if the variable geometry turbocharger actuator lever moves. For more information refer to: Turbocharger Drive Rod (303-04B Fuel supply and controls - turbocharger - ID4 2.4L diesel engine, Removal - Refitting). For turbocharger actuator checks: For more information refer to: Turbocharger (303-04B Fuel supply and controls - turbocharger - ID4 2.4L diesel engine, Removal - Refitting).
Engine stops/stops	Air leak Low/contaminated fuel Malfunction in the low pressure fuel system High pressure fuel leak Suction control valve failure EGR valve malfunction (EGR)	NOTE: Make sure the latest throttle inlet EGR valve is installed. Using the manufacturer's approved diagnostic system, check and install the latest software on the engine control unit. Check the air intake system for leaks. Check fuel level/condition. Drain approximately 1 liter of fuel and let it sit for 1 minute. Check that there is no separation indicating the presence of water or other liquid in the fuel. Check the fuel system for leaks/damage. Check for DTCs indicating a faulty injection pump. EGR valve checks: For more information, refer to: Emission Control (303-08 Emission Control -ID4 2.4L Diesel Engine, Diagnostics and Checks).
Engine vibration	Low/contaminated fuel Air intake Malfunction in the low pressure fuel system Suction control valve failure High pressure fuel leak High pressure fuel pump malfunction	Check fuel level/condition. Drain approximately 1 liter of fuel and let it sit for 1 minute. Check that there is no separation indicating the presence of water or other liquid in the fuel. Check air intake system for leaks. Check the low pressure fuel system for leaks/damage. Check the high pressure fuel system for leaks, check for DTCs indicating a faulty injection pump. Check high pressure fuel pump: For more information refer to: Fuel pump (303-04A Fuel supply and controls - Diesel engine ID4 2.4L, Removal and installation).
Excessive fuel consumption	# Malfunction in the low pressure fuel system Suction control valve failure Fuel temperature sensor leak High pressure fuel leak Injector failure (OK) EGR valve malfunction (EGR)	NOTE: Make sure the latest throttle inlet EGR valve is installed. Using the manufacturer approved diagnostic system, check and install the latest software on the engine control unit. Check the low pressure fuel system for leaks/damage. Check for DTCs indicating a faulty injection pump. Check the fuel temperature sensor, high pressure fuel pump, etc. for leaks. Check for injector related DTCs. EGR valve checks: For more information, see: Emission Control (303-08 Emission Control -ID4 2.4L Diesel Engine, Diagnostics and Checks).

See section 100-00 for a complete list of DTCs that can be logged in the vehicle. For more information, see: How to use this manual (100-00 General information, Description and principle of operation).