u1125 invalid or missing data for primary id

OBD2 Code: U1125

Description: Invalid or Missing Data for Primary ID

Definition: This code indicates that the vehicle’s control module has detected a loss of communication with the primary identification system, which could be due to a malfunction in the data network or an issue with one of the modules.

Invalid or missing data for primary id: Information not available – Unknown severity

Common Causes

Invalid or missing data for primary id:
– Loose connection in the wiring harness
– Faulty primary id sensor
– Corroded or damaged connectors

 

Common Misdiagnosis

Invalid or Missing Data for Primary ID

Common Misdiagnosis: Replacing the ECU (Engine Control Unit) without verifying wiring issues or communication faults between modules.

 

Common Diagnostic Steps

Invalid or Missing Data for Primary ID

• Check the vehicle’s battery and charging system for proper voltage levels.
• Inspect all related wiring and connectors for signs of damage, corrosion, or loose connections.
• Use a scan tool to check for any additional trouble codes that may be present.
• Verify the integrity of the communication network (CAN bus) by checking resistance values with a multimeter.
• Update or reprogram the vehicle’s control modules if necessary, following manufacturer guidelines.
• If applicable, inspect and test sensors associated with the primary ID for correct operation.