u1118 lost engine message

OBD2 Code: U1118

Description: Lost Engine Message

Definition: The OBD-II code U1118 indicates a communication problem between the vehicle’s control modules. Specifically, it means that the Powertrain Control Module (PCM) has lost communication with the engine control module or other related components. This can be due to wiring issues, faulty connectors, or a malfunctioning module.

– Lost Engine Message
Severity: Critical

Common Causes

Common causes of u1118 code:
– Faulty engine control module (ECM)
– Wiring issues between ECM and other modules
– Software issues with ECM or related modules

Common Misdiagnosis

OBD2 Code: U1118 – Lost Engine Message
Description: This code indicates a loss of communication with the engine control module (ECM).
Common Misdiagnosis: Replacing the ECM without checking for wiring issues or network problems.

Common Diagnostic Steps

Lost Engine Message

1. Check for any other stored trouble codes that might be related to communication issues.
2. Inspect the wiring and connectors between the engine control module (ECM) and the transmission control module (TCM) for any signs of damage, corrosion, or disconnection.
3. Test the battery voltage and charging system to ensure they are within specifications.
4. Use a scan tool to check for proper communication between modules on the CAN bus network.
5. Perform a continuity test on the CAN bus lines to identify any breaks or shorts in the circuit.
6. If equipped, update or reflash the ECM/TCM software as per manufacturer recommendations.
7. If all else fails, consider replacing faulty modules after confirming with diagnostic tests.