LCM Alert Validation

Confidence

Failure Category

Lighting

Subcategory

Recently Replaced Light

Sensor Verdict: The LCM sensor flagged the YELLOW (Left Turn) circuit on trailer V505491 at site RFD2. Based on the work order evidence, confidence is moderate (72%) that a real defect existed on this trailer — the volume of lighting repairs performed strongly suggests the trailer had legitimate electrical faults. However, the specific YELLOW/Left Turn circuit cannot be confirmed as the repaired circuit, as the vendor's documented work is focused entirely on marker and clearance lamps. There is a plausible indirect connection (marker lights on the left side of a trailer can share wiring or ground paths with the turn circuit), but no direct evidence ties the repairs to the alerting circuit.

Photo Evidence: No photos were provided with this work order. The LCM troubleshooting procedure explicitly required photos of each light illuminated, a clear nosebox wiring photo, and a TechAssist app screenshot showing green 'Verified' status for all five circuits. None of these were submitted. The absence of photographic documentation makes it impossible to independently verify the condition of the YELLOW circuit, the nosebox, or the state of repairs before and after the work was performed. This is a significant documentation deficiency.

Vendor Compliance: The vendor did not follow the prescribed LCM troubleshooting procedure. There is no indication the PCT TechAssist app was used at any point during diagnosis or repair. The technician notes are informal and do not reference circuit-level verification, TechAssist findings, or any of the required feedback categories from the troubleshooting protocol. The notes mention a 'light verification' was performed, but no structured or app-guided process is evident. The work order does not include a TechAssist completion screenshot, nor does it categorize findings using the required terminology (e.g., 'light missing,' 'wiring damage,' 'no defect found confirmed with PCT'). Overall vendor compliance with the LCM procedure is poor.

Repair Summary: The vendor replaced 5 marker/clearance lamp assemblies, installed 2 red mini LED marker lamps (part 33250R), replaced 2 grommets (part 33700), replaced 1 light pigtail, and used butt splice connectors and rivets to complete the installation. Tail lights were removed and reinstalled with rivets to access wiring. The parts used (Grote-compatible grommets and standard LED markers) appear to be acceptable components. However, none of the line items reference the YELLOW left turn circuit, tail lamps as turn signal sources, or any repair to a turn signal-specific component. A PCT sensor activation line item also appears on this work order, which may indicate a separate TPMS-related activity occurring simultaneously — this is unrelated to the LCM alert but adds noise to the work order.

Key Concerns: There are several notable concerns with this work order. First and most critically, the faulted YELLOW (Left Turn) circuit does not appear to have been directly addressed — all repairs are marker/clearance focused. Second, the PCT TechAssist app was not used and no verification screenshots were provided, which is a direct non-compliance with the troubleshooting protocol. Third, no photos of any kind were submitted, eliminating all visual verification of the repair or circuit condition. Fourth, the inclusion of a TPMS sensor activation line item on a lighting-focused work order raises questions about whether this vehicle visit was primarily for the LCM alert or a different issue, potentially diluting attention to the alerting circuit. Fleet reviewers should consider whether a follow-up inspection of the YELLOW circuit is warranted, and this vendor visit should be flagged for procedure non-compliance.