U1073 – OBD-II DTC

OBD-II DTC U1073 – SCP (J1850) Invalid or Missing Data for Engine Coolant

DTC U1073 meaning

DTC U1073 refers to a communication issue within the vehicle’s network, specifically indicating that the Engine Control Module (ECM) is not receiving valid or any data regarding the engine coolant temperature. This code is part of the On-Board Diagnostics II (OBD-II) system and is associated with the SCP (Serial Communication Protocol) using the J1850 protocol.

DTC U1073 symptoms

Common symptoms associated with DTC U1073 may include:

• Illumination of the Check Engine Light (CEL)
• Inaccurate engine coolant temperature readings
• Engine overheating or running too cool
• Potential performance issues or reduced fuel efficiency
• Other related DTCs may be present

DTC U1073 causes

Several factors can lead to the triggering of DTC U1073, including:

• Faulty engine coolant temperature sensor
• Wiring issues, such as damaged or corroded connectors
• Faulty Engine Control Module (ECM)
• Communication problems within the vehicle’s network
• Software glitches or programming errors

DTC U1073 seriousness

DTC U1073 can be considered serious as it may lead to engine performance issues and potential overheating. If the ECM cannot accurately monitor the engine coolant temperature, it may not adjust fuel delivery and ignition timing correctly, which can result in engine damage over time. It is advisable to address this code promptly to avoid further complications.

How to diagnose DTC U1073

To diagnose DTC U1073, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC U1073.
2. Check for any additional DTCs that may provide more context.
3. Inspect the engine coolant temperature sensor and its wiring for damage or corrosion.
4. Test the engine coolant temperature sensor using a multimeter to ensure it is functioning correctly.
5. Examine the vehicle’s communication network for any faults or interruptions.
6. Check the ECM for any software updates or known issues.

How to fix DTC U1073 step-by-step instructions

To fix DTC U1073, follow these steps:

1. Repair or replace any damaged wiring or connectors related to the engine coolant temperature sensor.
2. If the engine coolant temperature sensor is faulty, replace it with a new one.
3. Clear any stored DTCs using an OBD-II scanner.
4. Start the engine and allow it to reach operating temperature while monitoring the coolant temperature readings.
5. Check for the reappearance of DTC U1073 or any other related codes.
6. If the code returns, further diagnose the ECM and communication network.

How to erase DTC U1073

To erase DTC U1073, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase DTCs.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the engine to ensure the code does not return.

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