Diagnosis and check 4.0L (Discovery 3)

Inspection and verification

1. Check the validity of the customer's complaint. Be aware that the vehicle has a number of systems that communicate with the message center to provide the driver with information useful in diagnosing problems.

2. Perform a visual check for obvious signs of mechanical or electrical damage.

3. If an obvious cause of a problem you identified or described by a customer is found, resolve it before proceeding to the next steps (if possible).

4. Read all DTCs using an approved diagnostic system or scan tool before referring to the Symptom Chart or DTC Index. Clear all DTCs after troubleshooting.

Symptom table

NOTE: For a more complete table of symptoms, refer to Section 303-14 - "Electronic engine controls" in the workshop manual.

Symptom	Possible reason	Action
The crankshaft of the engine scrolls, there are flashes, but the engine does not start	EVAP purge valve Fuel system Spark plug Malfunction (And) ignition coils	For purge valve checks, refer to the guided diagnostic program on the approved diagnostic system. For fuel and ignition system checks, refer to the appropriate section in the workshop manual.
Difficult cold start	Check the concentration of antifreeze in the cooling system Battery crankshaft position sensor (CKP) Fuel system EVAP purge valve	Check the condition of the coolant. For battery information and information on CKP sensor and fuel system checks, refer to the appropriate section in the workshop manual. For purge valve checks, refer to the guided diagnostic program on the approved diagnostic system.
Difficulty starting when hot	Nozzle leak Fuel system Fuel temperature sensor Intake air temperature sensor (IAT) Mass air flow sensor (MAF) EVAP purge valve Ignition system	For information on injector and fuel system checks, fuel temperature sensor, IAT sensor, MAF sensor and ignition system, refer to the appropriate section in the workshop manual. For purge valve checks, refer to the guided diagnostic program on the approved diagnostic system.
Difficulty starting after a hot soak (the vehicle remains stationary for a while after the engine has reached operating temperature)	Nozzle leak Fuel system Fuel temperature sensor IAT sensor MAF sensor EVAP purge valve Ignition system	For information on injector and fuel system checks, fuel temperature sensor, IAT sensor, MAF sensor and ignition system, refer to the appropriate section in the workshop manual. For purge valve checks, refer to the guided diagnostic program on the approved diagnostic system.

DTC index

NOTE: Universal Scan Tools may not read the listed codes or may only read 5-digit codes. Match the 5 digits from the scan tool with the first 5 digits of the listed 7 digit code to identify the problem (the last 2 digits give additional information read by the approved diagnostic system).

NOTE: For a complete list of ECM DTCs, refer to Section 303-14 - "Electronic engine controls" in the workshop manual.

DTC	Description	Possible reason	Action
P040200	An increased flow rate has been registered in the exhaust gas recirculation system A	Exhaust gas recirculation valve (EGR) incorrectly installed or loose Blockage of the EGR pipeline EGR valve sticking Blockage of EGR heat exchangers Electrical circuit (And) EGR valve: high resistance Electrical circuit (And) EGR valve: short to ground Electrical circuit (And) EGR valve: short circuit to battery + EGR valve failure MAF sensor malfunction	Refer to the relevant section in the workshop manual. Check MAF sensor and circuits. Refer to the electrical manual.
P040500	Low Voltage EGR Sensor Circuit A	Electrical circuit (And) right EGR valve: high resistance Electrical circuit (And) EGR valve: short to ground EGR valve failure	Refer to the electrical manual and check the EGR valve circuit. Repair/replace as needed.
P040600	High Voltage EGR Sensor Circuit A	EGR valve circuit short to battery + EGR valve failure	Refer to the electrical manual and check the EGR valve circuit. Repair/replace as needed.
P040900	Electrical circuit A of the exhaust gas recirculation sensor	Range/Performance Problems, Differential Pressure Sensor Circuit Shorted EGR valve failure	Refer to electrical manual and check EGR valve sensor circuit (DIFF PRESS). Repair/replace as needed.
P044100	Fuel vapor control system - incorrect purge flow	Capacity limitation/leakage in the EVAP carbon canister purge valve line (EVAP) Reducing the capacity of the adsorber ventilation duct Purge valve failure	Check the integrity of the pipeline and the ventilation duct of the carbon adsorber. Refer to the relevant section in the workshop manual.
P044200	Leak detected in fuel vapor control system (small leakage)	Fuel filler cap incorrectly installed Filler cap seal failure Leak in the fuel vapor control system (adsorber, pipelines, etc.) Leak in the fuel tank Malfunction of the valve of the leak control system in the tank (DMTL)	Refer to the relevant section in the workshop manual.
P044700	Rupture of an electric chain of management of ventilation of system of catching of steams of fuel	EVAP DMTL valve circuit short circuit to ground	Refer to the electrical manual and check the electrical circuit of the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual.
P044800	Short circuit in the electrical ventilation control circuit of the fuel vapor control system	EVAP DMTL valve circuit short circuit to battery	Refer to the electrical manual and check the electrical circuit of the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual.
P045500	Leak detected in fuel vapor control system (big leak / no flow)	Fuel filler cap not installed Damaged/missing fuel filler cap seal Leak in the fuel vapor control system (adsorber, pipelines, etc.) Leak in the fuel tank DMTL valve failure	Check the fuel filler cap and seal, check the canister, piping, etc. Check the fuel tank for leaks, etc. Refer to the relevant section in the workshop manual.
P045800	EVAP Purge Control Valve Circuit Low Voltage	Purge valve control circuit short to ground Purge valve control circuit high resistance Malfunction of the valve of a purge of an adsorber EVAP	Refer to the electrical manual and check the electrical circuit of the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual. Refer to the guided diagnostic program for this code on the approved diagnostic system.
P045900	High voltage in the electrical circuit of the evaporative emission system purge control valve	Purge valve control circuit short to battery	Refer to the electrical manual and check the electrical circuit of the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual. Refer to the guided diagnostic program for this code on the approved diagnostic system.
P240100	Low voltage in the electric control circuit of the leak control pump in the fuel vapor control system	Electrical circuit (And) tank leak control pump (DMTL): short circuit to ground Electrical circuit (And) pump DMTL: high resistance	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P240200	High voltage in the electric control circuit of the leak control pump in the fuel vapor control system	Electrical circuit (And) tank leak control pump (DMTL): short circuit to + battery	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P240429	Problems with the operating range / characteristics of the electric circuit of the sensing of the leak control pump in the fuel vapor control system	Reference leak of tank leak monitoring system (DMTL)	Check the fuel vapor control system for function and leaks. Check DMTL pump and electrical circuits. Refer to the electrical manual. Perform a DMTl check. Refer to the relevant section in the workshop manual.
P24042F	Problems with the operating range / characteristics of the electric circuit of the sensing of the leak control pump in the fuel vapor control system	Chaotic signal of the tank leak monitoring system (DMTL)	Check DMTL pump and electrical circuits. Refer to the electrical manual. Refer to the relevant section in the workshop manual.
P240500	Low voltage in the electrical circuit of the perception of the leak control pump in the fuel vapor control system	Tank leak control pump circuit (DMTL): reference circuit low voltage	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P240600	High voltage in the electrical circuit of the perception of the leak control pump in the fuel vapor control system	Tank leak control pump circuit (DMTL): reference circuit high voltage	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P240B00	Low voltage in the electric circuit of the heating element of the leak control pump in the fuel vapor recovery system	Low voltage in the electric control circuit of the heating element of the tank leakage monitoring system (DMTL)	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P240C00	High voltage in the electric circuit of the heating element of the leak control pump in the fuel vapor control system	High voltage in the electric control circuit of the heating element of the tank leakage monitoring system (DMTL)	Refer to the electrical manual and check the wiring between the ECM and the DMTL pump. Repair if necessary.
P245000	Performance Problems/Stuck Open Multi-Way Evaporative Control Valve	Tank leak control pump circuit (DMTL): short circuit, high resistance DMTL switching valve failure	Refer to the electrical manual and check the wiring between the ECM and the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual.
P245100	Stuck closed multi-way valve of the fuel vapor control system	Tank leak control pump circuit (DMTL): short circuit, high resistance DMTL switching valve failure	Refer to the electrical manual and check the wiring between the ECM and the DMTL valve. Repair/replace as needed. Refer to the relevant section in the workshop manual.