u1198 invalid or missing data for external access
OBD2 Code: U1198
Description: Invalid or Missing Data for External Access
Definition: This code indicates that there is a communication issue within the vehicle’s network, where data from an external module or system is either not being received correctly or is missing entirely. This can affect various systems that rely on shared data across the vehicle’s network.
U1198 – Invalid or Missing Data for External Access
Severity: Moderate
Common Causes
U1198 – Invalid or Missing Data for External Access
Common causes include:
- Issues with the vehicle’s communication network
- Faulty wiring or connectors in the data link connector (DLC)
- Problems with the OBD2 system itself, such as a malfunctioning control module
Common Misdiagnosis
Common Misdiagnosis: Faulty wiring or connectors, rather than an issue with the external access module itself.
Common Diagnostic Steps
- Check the vehicle’s battery and charging system to ensure proper voltage levels.
- Inspect all related wiring and connectors for signs of damage, corrosion, or loose connections.
- Use a scan tool to check for other related codes that might indicate a broader issue with the communication network.
- Verify the integrity of the CAN bus network by checking resistance values at the diagnostic connector.
- Test any suspect modules or sensors that may be involved in external data access for proper operation.
- If applicable, update or reprogram any control modules with the latest software from the manufacturer.