DTC B12F4-12: Vehicle Speed Output - Circuit short to battery: Action
WARNING: This page is about a different car, the 2018 Land Rover Discovery and 2017 Land Rover Discovery. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
To validate the repair use the Jaguar Land Rover approved diagnostic equipment to perform the routine - On Demand Self Test. If the repair is successful this DTC will no longer be logged within the body control module. Alternatively run the engine for at least 30 seconds and check the accessory road speed function, then use the Jaguar Land Rover approved diagnostic equipment to check this DTC is no longer logged in the body control module
- Firstly disconnect any accessories or aftermarket systems connected to the accessory speed signal, then using the Jaguar Land Rover approved diagnostic equipment run the application - On Demand Self test. If the DTC is still present, refer to the electrical circuit diagrams and check the accessory road speed signal circuit for short circuit to power. Repair the wiring harness as necessary