B2485

Code

Other B — Body

LF SIDE REPEATER LAMP OUTPUT Ckt Short to Battery

Brand: Other

Type: B — Body

Views: UK: 22 EN: 36 RU: 31

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Damaged wiring harness where the LF lamp output conductor contacts a constant battery feed
Corroded or bridged connector pins at the LF lamp or intermediate connector
Shorted or miswired aftermarket accessory or trailer wiring
Failed lamp assembly or LED driver causing an internal short to battery
Faulty body control module (BCM) or lamp driver transistor (less common)

Scan for stored codes and note freeze-frame or related lamp/body codes
Visual inspection of LF lamp, lens, mounting, and wiring harness for damage or corrosion
Disconnect LF lamp assembly — check if code clears or symptom changes
Back-probe LF lamp output connector and measure voltage with switch ON and OFF
Check continuity between output pin and battery positive (should not be continuous when off)
Inspect for aftermarket wiring/tow harness tied into repeater circuit

Expected: ~0 V at LF output with lights/turn off; ~battery voltage (11–14 V) when commanded ON
Fault: battery voltage present at LF output when command is OFF (indicates short to battery)
Resistance: high/open between LF output and battery positive with circuit off; low resistance indicates short
Current: abnormal continuous current draw on the lamp circuit when OFF (value depends on lamp type; LEDs draw low current but short may allow full battery current)

Read and record DTC(s) and any related freeze frame data. Confirm exact lamp function affected (repeater/turn/marker).
Perform a careful visual inspection of the LF lamp, connector, and harness for chafing, corrosion, or aftermarket splices.
With ignition off, disconnect the LF repeater lamp connector. Clear the code and verify whether the DTC returns or the symptom changes. If code clears with connector unplugged, suspect lamp assembly or wiring downstream.
Back-probe the LF lamp output at the connector. With the output commanded OFF, measure voltage to chassis ground and to battery positive. Battery voltage present when OFF indicates a short to battery.
If voltage indicates a short, isolate by unplugging intermediate connectors or sections of harness and re-check until the shorted section is found.
Inspect and repair the damaged wire, connector, or replace corroded lamp assembly. Remove any aftermarket taps or correct their wiring.
If wiring and lamp are good, perform module output tests per service manual (measure driver transistor behavior, compare to vehicle-specific expected values) and consider BCM replacement only after wiring and lamp verified.
After repair, clear codes and test all related lamp functions, verify no reoccurrence, and check for parasitic drain if lamp had been powered while vehicle off.

Chafed wiring rubbing against a fused battery feed or constant hot circuit
Water intrusion/corrosion in LF lamp connector creating conductive path to battery
Aftermarket harness tied into constant battery instead of switched output
Internal short in an LED repeater assembly or its resistor/driver
Damaged insulation near junctions or under body trim causing contact with hot feed