What does it mean?
B2500 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Left Power Sliding Door Latch Cinch Overcurrent .
Symptoms
- Interior lights stay on and will not switch off, even with the doors closed and the vehicle locked
- Interior lights do not respond to the door switches or the dimmer control
- The battery goes flat overnight
- Courtesy lamps come on by themselves after the vehicle has been left locked
- Interior lighting is disabled entirely once the module protects the output
Likely causes
- Courtesy lamp output wire shorted to a permanent live circuit in the roof or pillar loom
- Aftermarket interior lighting, a dash camera or an alarm wired into the courtesy lamp feed
- Corrosion in the roof console connector after a sunroof drain or windscreen leak
- Loom trapped or pierced during headlining, pillar trim or roof console work
- Interior lamp unit with an internal short to its own supply
- Non standard LED interior bulbs feeding current back into the output
- Body control module output driver stuck on
How to fix it
- With the doors closed and the lamps commanded off, measure the courtesy lamp output at the module for unwanted voltage
- Remove the interior lamp assemblies one at a time and watch whether the reading changes, which isolates a shorted lamp unit
- Disconnect any aftermarket lighting or accessories connected to the interior lamp circuit and retest
- Check the roof and pillar loom for water damage from a sunroof drain or a leaking windscreen
- Inspect any area where trim has been removed for a trapped or pierced wire
- Refit original type bulbs where LED replacements have been fitted
- Repair the shorted wiring, then confirm the lamps switch off correctly and the parasitic current draw returns to normal