U0307
Software Incompatibility with Glow Plug Control Module
- Severity
- High
- Driving
- Drive only to a garage
The software in the glow plug control module is not compatible with the rest of the vehicle. Whatever that module runs is no longer being coordinated correctly, so expect a limp-home mode, a fixed gear, a refusal to start, or the loss of the function it controls. The module itself is working - it is the version of its software, or its configuration for this particular vehicle, that is wrong.
Possible causes
- CommonThe glow plug control module replaced but never programmed or coded to this vehicle
- CommonUsed module fitted from a different vehicle, model year or engine variant
- CommonSoftware update interrupted, often by battery voltage falling during programming
- CommonOne module updated while others were left at their old versions
- CommonWrong part number - physically identical, electronically different
- PossibleAftermarket remap or tuning device
- RareCorrupted module software
What you might notice
- Limp-home mode or reduced power
- Transmission stuck in one gear
- Engine will not start
- Several warning lights at once
- Function controlled by that module unavailable
- Fault present since a repair or service visit
What to check, in order
- Ask what was done to the vehicle recently, and by whom. This code follows work; it does not appear on its own.
- Read the software and part numbers of the glow plug control module and compare them against the vehicle's build specification - not just the model, but the engine variant, market and model year.
- If a used module was fitted, check whether it is locked to its original vehicle. Many are, and it is better to find that out before paying for programming.
- If a programming session was interrupted, it can usually be re-run with a battery support unit connected so voltage cannot fall again.
- Do not replace the module. It is almost always the right hardware carrying the wrong software.
- Expect manufacturer-level programming. A generic scan tool can read this code but cannot fix it, and neither can Pin16's coding lane, which writes documented parameters rather than module software.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
U00xxU01xxU02xxU03xxU04xxU05xxU06xxU07xxU08xxU09xxU0AxxU0BxxU0CxxU0DxxU0ExxU0FxxU10xxU11xxU12xxU13xxU14xxU15xxU16xxU17xxU18xxU19xxU1AxxU1BxxU1CxxU1DxxU1ExxU1FxxU20xxU21xxU22xxU23xxU24xxU25xxU26xxU27xxU28xxU29xxU2AxxU2BxxU2CxxU2DxxU2ExxU2FxxU30xxU31xxU32xxU33xxU34xxU35xxU36xxU37xxU38xxU39xxU3AxxU3BxxU3CxxU3DxxU3ExxU3Fxx