U1112 - INVALID OR MISSING DATA FOR PRIMARY ID
POST UPDATED IN February, 2023
U1112 Code failures by brands
Description of DTC code U1112
Control Modules that connect to the Class 2 serial data circuit monitor serial data communications when the vehicle operation is stable. Exchanges of commands and operating data occur between the modules. When a controller receives a message signaling erratic performance, the controller logs a reporting module ID Code for the status of the health monitoring/live node messages.
In order to define a parameter as erratic or critical, it must not be received. Therefore, the controller uses a default value for that parameter. Once a module learns the Identification Code, it will monitor the live node message from the controller.
The DTC U1112 OBD2 setting occurs if a module does not relate an Identification Code with at least one critical parameter during a period of 5 seconds after the start of serial data communication.
Symptoms of fault code U1112
- Check Engine light ON.
Causes of OBD2 U1112
The U1112 OBDII diagnostic code is stored for the following reasons:
- The Control Module wires that do not communicate may be in poor condition.
- The Control Module circuit may have poor connections.
- The Control Module may be faulty.
Possible solutions of the DTC code U1112
Steps to troubleshoot the U1112 OBD2 fault code:
- Consult the Technical Service Bulletins (TSB).
- Check with a scanner if there are other DTCs stored next to the U1112, which may indicate problems with a specific module. In this case, the diagnosis should be done in the order listed.
- Check for deficiencies in the wiring and connections of the non-communicating Control Module. If you discover excessive levels of corrosion or burn points, make adjustments accordingly.
