U0305 — Software Incompatibility with Cruise Control Module
A control module has detected that its software/calibration is incompatible with the cruise control module. Cruise control may be disabled until matching software is flashed.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Cruise control module
- Control module
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Software/calibration mismatch with cruise module
- Used cruise module from different vehicle fitted
- Gateway module routing CAN messages incorrectly
Possible symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Diagnostic notes
- The malfunction indicator lamp may illuminate
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.