Diagnostics and testing 2.7L (Discovery 3)

Inspection and verification

1. Ensure that the customer's complaint is justified.

2. Visually inspect for obvious mechanical and electrical problems.

Mechanical factors	Electrical factors
Leaks Metal fatigue Pipes Catalytic converter Silencer(s) Connections Supports Clearance around elements	Fuses and fuses Wiring harness Electrical connector(s) Sensor(s) Engine Control Module (ECM)

3. If an obvious cause for the problem you identified or the customer described is found, resolve it before moving on to further action. (if possible).

4. Use the approved diagnostic system or scan tool to retrieve all diagnostic trouble codes (DTCs) before referring to the symptom chart or DTC index.

Clear all DTCs after troubleshooting.

Table of signs of malfunction

Sign of malfunction	Possible reasons	Action
Noise or leaks in the exhaust system	Exhaust system/system elements	If necessary, install new elements. Refer to the relevant section in the service station manual.
Insufficient power	Air intake system malfunction Clogged exhaust system Low fuel pressure	Check the air intake system. Check the muffler or catalytic converter for blockages, install new components if necessary. Check the fuel system pressure. Refer to the relevant section in the service station manual.

DTC Index

NOTE: Generic scan tools cannot read the codes listed or can 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 fault. (the last 2 digits provide additional information readable by a manufacturer approved diagnostic system).

[The source of the article is located on the website: www.LRman.ru]

NOTE: For a complete listing of ECM DTCs, refer to Section 303-14, Electronic Engine Control System, in the service manual.

DTC codes	Description	Possible reasons	Action
P042562	Catalytic Converter Temperature Sensor Circuit (cylinder bank 1, sensor 1 electrical circuit)	Error when comparing the signal from the temperature sensor before the catalytic converter (right bank of cylinders, sensor 1) Compare the correlation of the temperature sensor before the catalytic converter with at least two other sensors Malfunction of the temperature sensor before the catalytic converter Pre-Catalytic Converter Temperature Sensor Signal Circuit - Short to Ground, Short to Battery or Open Circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the pre-catalytic converter temperature sensor circuit for short to ground or voltage, or open circuit. Check the pre-catalytic converter temperature sensor for dirt, corrosion, or water damage. Replace the pre-catalytic converter temperature sensor.
P042600	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Error checking the signal gradient from the temperature sensor before the catalytic converter (right bank of cylinders, sensor 1) Malfunction of the temperature sensor before the catalytic converter Pre-Catalytic Converter Temperature Sensor Signal Circuit - Short to Ground, Short to Battery or Open Circuit Pre-Catalytic Converter Temperature Sensor Circuit High Resistance	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the pre-catalytic converter temperature sensor circuit for a short to ground or battery voltage, open circuit, poor connection. Install a new sensor as necessary.
P04261A	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Pre-Catalytic Converter Temperature Sensor Circuit Resistance Below Threshold (right bank of cylinders, sensor 1) Plausibility of the temperature sensor signal before the catalytic converter during cold start, too high temperature difference Pre-Catalytic Converter Temperature Sensor: High Temperature Value Stuck	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the pre-catalytic converter temperature sensor circuit for low resistance, short to ground. Replace the pre-catalytic converter temperature sensor.
P04261B	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Pre-Catalytic Converter Temperature Sensor Circuit Resistance Above Threshold (right bank of cylinders, sensor 1) Plausibility of the temperature sensor signal before the catalytic converter during cold start, too low temperature difference Pre-Catalytic Converter Temperature Sensor: High Temperature Value Stuck	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the pre-catalytic converter temperature sensor circuit for high resistance, open circuit. Replace the pre-catalytic converter temperature sensor.
P04261E	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Pre-Catalytic Converter Temperature Sensor Circuit Resistance Out of Range (right bank of cylinders, sensor 1) Plausibility of the temperature sensor signal before the catalytic converter with the engine running, too low temperature Pre-Catalytic Converter Temperature Sensor: Low Temperature Stuck	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the pre-catalytic converter temperature sensor circuit for a short to ground or voltage, or an open circuit. Check the pre-catalytic converter temperature sensor for dirt, corrosion, or water damage. Replace the pre-catalytic converter temperature sensor.
P042700	Catalytic Converter Temperature Sensor Circuit Low Voltage (cylinder bank 1, sensor 1 electrical circuit)	Pre-Catalytic Converter Temperature Sensor Signal Below Minimum Voltage Threshold (right bank of cylinders, sensor 1) Malfunction of the temperature sensor before the catalytic converter Pre-Catalytic Converter Temperature Sensor Circuit Short to Ground	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the pre-catalytic converter temperature sensor circuit for a short to ground. Install a new sensor as necessary.
P042800	Catalytic Converter Temperature Sensor Circuit High Voltage (cylinder bank 1, sensor 1 electrical circuit)	Pre-Catalytic Converter Temperature Sensor Signal Above Maximum Voltage Threshold (right bank of cylinders, sensor 1) Malfunction of the temperature sensor before the catalytic converter Electrical circuit of temperature sensor before catalytic converter - short circuit to + battery, open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the pre-catalytic converter temperature sensor circuit for short to battery, open circuit. Install a new sensor as necessary.
P042A62	Catalytic Converter Temperature Sensor Circuit (cylinder bank 1, sensor electrical circuit 2)	Error when comparing signal from temperature sensor after catalytic converter (right bank of cylinders, sensor 2) Comparison of the post-catalytic converter temperature sensor correlation with at least two other sensors Malfunction of the temperature sensor after the catalytic converter Post Catalytic Converter Temperature Sensor Signal Circuit - Short to Ground, Short to Battery or Open Circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the post catalytic converter temperature sensor circuit for short to ground or voltage, or open circuit. Check the post catalytic converter temperature sensor for dirt, corrosion, or water damage. Replace the post catalytic converter temperature sensor.
P042B00	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Error checking the gradient of the signal from the temperature sensor after the catalytic converter (right bank of cylinders, sensor 2) Malfunction of the temperature sensor after the catalytic converter Post Catalytic Converter Temperature Sensor Signal Circuit - Short to Ground, Short to Battery or Open Circuit Post Catalytic Converter Temperature Sensor Circuit High Resistance	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the post catalytic converter temperature sensor circuit for a short to ground or battery voltage, open circuit, poor connection. Install a new sensor as necessary.
P042B1A	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Post-Catalytic Converter Temperature Sensor Circuit Resistance Below Threshold (right bank of cylinders, sensor 2) Plausibility of the temperature sensor signal after the catalytic converter during cold start, too high temperature difference Temperature sensor after catalytic converter: fixation at high temperature value	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the post catalytic converter temperature sensor circuit for low resistance, short to ground. Replace the post catalytic converter temperature sensor.
P042B1B	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Post-Catalytic Converter Temperature Sensor Circuit Resistance Above Threshold (right bank of cylinders, sensor 2) Plausibility of the temperature sensor signal after the catalytic converter during cold start, too low temperature difference Temperature sensor after catalytic converter: fixation at high temperature value	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the post catalytic converter temperature sensor circuit for high resistance, open circuit. Replace the post catalytic converter temperature sensor.
P042B1E	Catalytic Converter Temperature Sensor Circuit Range/Performance Problem (cylinder bank 1, sensor 1 electrical circuit)	Post Catalytic Converter Temperature Sensor Circuit Resistance Out of Range (right bank of cylinders, sensor 2) Plausibility of the temperature sensor signal after the catalytic converter with the engine running, too low temperature Post Catalytic Converter Temperature Sensor: Low Temperature Stuck	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the post catalytic converter temperature sensor circuit for short to ground or voltage, or open circuit. Check the post catalytic converter temperature sensor for dirt, corrosion, or water damage. Replace the post catalytic converter temperature sensor.
P042C00	Catalytic Converter Temperature Sensor Circuit Low Voltage (cylinder bank 1, sensor electrical circuit 2)	Post Catalytic Converter Temperature Sensor Signal Below Minimum Voltage Threshold (right bank of cylinders, sensor 2) Malfunction of the temperature sensor after the catalytic converter Post Catalytic Converter Temperature Sensor Circuit Short to Ground	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the post catalytic converter temperature sensor circuit for a short to ground. Install a new sensor as necessary.
P042D00	Catalytic Converter Temperature Sensor Circuit High Voltage (cylinder bank 1, sensor electrical circuit 2)	Post Catalytic Converter Temperature Sensor Signal Above Maximum Voltage Threshold (right bank of cylinders, sensor 2) Malfunction of the temperature sensor after the catalytic converter Electrical circuit of temperature sensor after catalytic converter - short circuit to + battery, open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the post catalytic converter temperature sensor circuit for short to battery, open circuit. Install a new sensor as needed.
P242A62	Exhaust Gas Temperature Sensor Circuit - Bank 1 Sensor 3	Error when comparing signal from temperature sensor after DPF (right bank of cylinders, sensor 3) Comparison of the correlation of the temperature sensor after DPF with at least two other sensors Temperature sensor after DPF faulty	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPF temperature sensor circuit for short to ground or battery, open circuit. Check the DPF temperature sensor for dirt, corrosion, water damage. Replace the DPF temperature sensor.
P242B1A	Exhaust Gas Temperature Sensor Circuit Range/Performance Problem - Bank 1 Sensor 3	Post DPF Temperature Sensor Circuit Resistance Below Threshold (right bank of cylinders, sensor 3) Plausibility of temperature sensor signal after DPF during cold start, too high temperature difference Temperature sensor after DPF faulty Temperature sensor after DPF: fixation at high temperature value	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the DPF temperature sensor circuit for low resistance, short to ground. Replace the DPF temperature sensor.
P242B1B	Exhaust Gas Temperature Sensor Circuit Range/Performance Problem - Bank 1 Sensor 3	Post DPF Temperature Sensor Circuit Resistance Above Threshold (right bank of cylinders, sensor 3) Plausibility of temperature sensor signal after DPF during cold start, temperature difference too low Temperature sensor after DPF faulty Temperature sensor after DPF: fixation at high temperature value	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the DPF temperature sensor circuit for high resistance, open circuit. Replace the DPF temperature sensor.
P242B1E	Exhaust Gas Temperature Sensor Circuit Range/Performance Problem - Bank 1 Sensor 3	Post DPF Temperature Sensor Circuit Resistance Out of Range (right bank of cylinders, sensor 3) Plausibility of the temperature sensor signal after DPF with the engine running, too low temperature Temperature sensor after DPF faulty Temperature sensor after DPF: fixation at low temperature value	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPF temperature sensor circuit for short to ground or battery, open circuit. Check the DPF temperature sensor for dirt, corrosion, water damage. Replace the DPF temperature sensor.
P242C00	Low Voltage in Exhaust Gas Temperature Sensor Circuit - Bank 1 Sensor 3	Post DPF temperature sensor signal below minimum voltage threshold (right bank of cylinders, sensor 3) Temperature sensor after DPF faulty Post DPF Temperature Sensor Circuit Short to Ground, High Resistance	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPF temperature sensor circuit for high resistance, short to ground. Install a new sensor as necessary.
P242D00	Exhaust Gas Temperature Sensor Circuit High Voltage - Bank 1 Sensor 3	Post DPF temperature sensor signal above maximum voltage threshold (right bank of cylinders, sensor 3) Temperature sensor after DPF faulty Electrical circuit of temperature sensor after DPF - short circuit to + battery, open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the post DPF temperature sensor circuit for short to battery, open circuit. Install a new sensor as necessary.
P242E00	Intermittent Malfunction/ Erratic Signal in Exhaust Gas Temperature Sensor Circuit - Bank 1, Sensor 3	Error checking the gradient of the signal from the temperature sensor after the DPF (right bank of cylinders, sensor 3) Temperature sensor after DPF faulty Electrical circuit of temperature sensor signal after DPF - short circuit to ground, short circuit to + battery or open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the electrical circuit of the temperature sensor after DPF for a short to ground or + battery, open circuit Poor connection. Install a new sensor if necessary.
P242F68	Clogging of the diesel fuel combustion product filter - accumulation of soot	DPF filter related event information DPF filter is partially clogged Internal short circuit in DPF circuit at ECM	The DPF filter needs to be regenerated. Please refer to the operating manual.
P244A00	Too low differential pressure across diesel particulate filter (bank 1)	Too low differential pressure across diesel fuel product filter - right cylinder bank	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPS circuit for short to ground or battery, open circuit. Check the external DPS system lines for leaks and damage. Check the internal DPF element for damage. Install the DPF according to specifications.
P244B00	Too high differential pressure across diesel particulate filter (bank 1)	Too high differential pressure across diesel fuel combustion product filter - right cylinder bank Diesel Particulate Filter - Internal Failure	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Contact your dealer for technical support.
P245300	Diesel Particulate Filter Pressure Sensor A Circuit Range/Performance Problem	DPS Stuck DPS - short to ground, short to battery + or open circuit Plausibility of the signal from the differential pressure sensor on the diesel fuel combustion product filter before starting The DPS system is dirty or clogged	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPS circuit for short to ground or voltage, open circuit. Check the DPS system for contamination or obstruction. Check for sticking of the DPS. Install the sensor according to specifications.
P245329	Diesel Particulate Filter Pressure Sensor A Circuit Range/Performance Problem	DPS signal is not normal Checking the plausibility of the differential pressure sensor signal on the diesel fuel combustion product filter during engine operation The DPS system is dirty or clogged DPS Stuck DPS - short to ground, short to battery + or open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPS circuit for short to ground or battery, open circuit. Check the DPS system for contamination or obstruction. Check the external DPS lines for leaks and damage. Check for binding of the DPS. Install the sensor according to specifications.
P245400	Low Voltage in Diesel Particulate Filter Pressure Sensor A Circuit	DPS signal below minimum threshold DPS failure DPS Circuit Short to Ground, High Resistance	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and test the DPS circuit for a short to ground and high resistance. Install the sensor in accordance with the specifications.
P245500	High Voltage in Diesel Particulate Filter Pressure Sensor A Circuit	DPS signal is above the maximum threshold DPS failure DPS electrical circuit - short circuit to battery +, open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPS circuit for short to battery, open circuit. Install the sensor in accordance with the specifications.
P245600	Intermittent malfunction/interruption in electrical circuit of diesel particulate filter pressure sensor A	Implausibility of the DPS signal gradient DPS failure DPS electrical circuit - short to ground, short to battery + or open circuit	Perform a pinpoint test for this DTC using the manufacturer approved diagnostic system. Refer to the electrical circuit diagrams and check the DPS circuit for a short to ground or battery, open circuit. Install the sensor in accordance with the specifications.
P245800	Diesel fuel product filter regeneration time	Regeneration Delay Timer Setting Out of Limit Internal short circuit in DPF circuit at ECM	Please contact your dealer's technical support.