What does it mean?
B2599 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Door Module Front Right .
Symptoms
- Passenger window, mirror or lock does not respond to the local switch
- Passenger window cannot be operated from the driver's master switch panel
- Passenger mirror will not adjust while the driver mirror still works
- Door lock or unlock behaves inconsistently on that door
- Scan tool cannot establish communication with the front right door module
- Faults come and go, sometimes returning after wet weather
Likely causes
- Moisture entering the passenger door and reaching the module or its connector
- Corroded terminals in the door jamb connector after repeated exposure to rain and washing
- Broken supply, ground or bus wire inside the flexible harness that crosses to the passenger door
- Blown fuse or a poor ground point feeding that module
- Communication failure on the bus so the module cannot be reached by the body controller
- Damage during previous door speaker, glass or lock actuator work with a connector left unlatched
- Internal electronic failure of the passenger door module
How to fix it
- Attempt communication with the front right door module using a scan tool to confirm whether it is on the bus
- Check the fuse supplying that module and any shared ground point behind the trim
- Remove the passenger door trim and vapour barrier and look for water, corrosion and wet insulation around the module
- Measure supply and ground at the module connector while opening and closing the door
- Test bus wiring continuity through the door boot and flex the harness while measuring
- Repair broken conductors and corroded pins and reseal the vapour barrier and grommet properly
- Replace and configure the door module only after wiring, power and ground are all proven