OBD-II code · Network
U0309 Software Incompatibility With Alternative Fuel Control Module
A module reports a software version mismatch with the alternative fuel (CNG/LPG/H2) control module — typically after replacing one of the modules without programming the new unit to match the rest of the network.
Is it safe to drive with U0309?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyModule replaced without programming
- PossibleWrong part number for the vehicle
- Less likelyGateway module routing CAN messages incorrectly
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
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–2 h
- Emissions test
- Likely to fail
- Parts involved
- Alternative Fuel Module
Related codes
- U0306Software Incompatibility with Fuel Injector Control Module
- U0307Software Incompatibility with Glow Plug Control Module
- U0308Software Incompatibility with Body Control Module
- U030ASoftware Incompatibility With Evaporative Emission System Leak Detection Control Module
- U030BSoftware Incompatibility With Glow Plug Control Module 2
- U030CSoftware Incompatibility With Reductant Quality Module
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.