What does it mean?
B1615 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Panel Illumination Control Circuit Open .
Symptoms
- Rear wiper is dead even though the motor and its fuse are good
- Rear wiper runs while the rear glass or tailgate is open and the blade strikes the trim or body
- The disable function works only sometimes as the tailgate is moved
- The fault is worse in wet weather and improves once the tailgate area dries
- On the illumination variant, dash and switch backlighting is completely out while all other lighting works
Likely causes
- Faulty rear wiper disable switch, which on many designs is mounted on the tailgate or the rear glass hinge
- Broken wire in the tailgate hinge conduit, where the loom flexes on every opening
- Water and corrosion in the tailgate connector
- Rear glass or tailgate latch misadjusted so the disable switch stays operated
- Corroded ground return for the switch
- Module input stage failure
- On applications where this code refers to panel lighting, an open illumination control circuit from a broken wire, an unplugged cluster or a failed driver
How to fix it
- Watch the disable input in live data while opening and closing the tailgate or rear glass and note whether the state changes
- Unplug the switch and jumper the circuit to confirm the module reads the change, which separates switch from module
- Inspect the harness in the tailgate hinge conduit for broken strands, as this is the usual failure point on rear glass circuits
- Check the connector for water and green corrosion, and reseal it after repair
- Test the switch for continuity when operated and check its mechanical adjustment against the latch
- Repair the wiring or replace the switch, then confirm the wiper stops with the glass open
- On the illumination variant, check continuity from the module to the lamps and confirm the cluster and panel connectors are fully seated