Trailer lights not working or ABS warning on?
A trailer lighting failure and an ABS warning are different service concerns, even when noticed together. State which lights or functions are affected and record the exact warning. This guide does not establish whether the combination is roadworthy.
Application & limits
Commercial trailers and their tractor connection. This page is booking information, not an ABS diagnostic chart or roadworthiness assessment.
What the symptom or code tells you
A cab or trailer warning needs to be matched to the installed system and trailer. Report tractor and trailer unit numbers, any recent coupling and whether the symptom changed before the vehicle was secured.
BC pre-trip and air-brake duties still apply. Do not treat an ABS lamp as proof of a wheel sensor failure, or assume that working stop lamps confirm the braking system is sound.
Information to send
Use details already available from the normal operator position or your records. Do not run a test or approach a hazard to collect them.
- Tractor and trailer make/year, fleet unit and ABS system identity if already known.
- Exact warning and codes with FMI, if displayed.
- Which running, turn, stop or marker lamps are affected.
- Recent harness/connector work, coupling history and a safe yard location.
What the mechanic assesses
The mechanic separates lighting/power/ground concerns from ABS diagnostics and uses the installed brake-equipment procedure. Tell us if there are also low-air, brake-release or dragging symptoms so the request is not limited to lamp work. Scope, parts and access are confirmed before arrival.
Prepare a repair request
Text the machine or vehicle, exact symptom and location. We confirm scope, safe access, parts needs, pricing and availability before a visit.
Serving Langley, Port Kells and the Lower Mainland service area. Readers elsewhere can use the source references and contact a qualified local service provider.
Related service & guides
Sources & applicability
Editorial update: . Public manufacturer and authority references checked on this date. Current vehicle-specific procedures and superseding information must be matched to the actual application before diagnosis or repair.
- ICBC air-brake training
ICBC commercial and air brake training, undated public guidance. BC operator training and pre-trip requirements remain applicable.
- Bendix TABS-6 Advanced service data SD-13-47671
Archived 2025 manufacturer service data for the TABS-6 Advanced single-channel trailer ABS. Power, lamp and DTC concerns are distinct; match the installed module and current procedure.