What does it mean?
B2525 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Turn Signal RH Rear Circuit Short to Ground .
Symptoms
- Right rear indicator stays dark when signalling and with the hazards on
- Rear lighting fuse blows, sometimes taking brake or number plate lamps with it
- Indicator flash rate abnormal or indicators disabled on that side after a few flashes
- Lamp failure message displayed in the cluster
- Problem tracks the weather, appearing after rain and clearing when dry
- Visible moisture inside the right rear lens
Likely causes
- Water pooling in the right rear lamp housing and shorting the socket to its shell
- Corroded socket terminals swollen with oxide and touching each other
- Rear harness rubbed through at the wheel arch, quarter panel edge or boot hinge grommet
- Trailer light harness or a rear camera installation spliced into the right indicator wire
- Incorrect or oversized bulb causing the socket to overheat and short internally
- Harness pinched by trim panels or cargo in the luggage area
- Failed lamp output driver in the rear body module
How to fix it
- Take out the right rear lamp assembly and check for water, damaged seals and blocked drain holes
- Inspect the socket and bulb base for corrosion, arcing and contacts touching the shell
- Unplug the lamp and measure from the indicator feed to ground to see whether the short is in the lamp or the harness
- Work the rear harness at the wheel arch and hinge while monitoring the meter for an intermittent short
- Remove trailer or accessory splices from the rear lighting circuit and retest
- Fit a new socket, dry and seal the housing, then install a bulb of the correct rating
- Only after the wiring is proven good should the rear module output be evaluated