LCM Alert Validation

Confidence

Failure Category

Lighting

Subcategory

light failure

Sensor Verdict: The LCM RED (Brake) circuit alert is confirmed as a genuine defect with high confidence (92%). The technician's diagnostic findings directly corroborate the sensor alert: the brake circuit initially produced open/erratic readings at the nosebox, which were traced to a faulty 7-way receptacle. Additionally, a Grote rear strobe brake light was found non-functional on the same circuit, representing a compound failure. Both issues fall squarely within the RED circuit's scope, validating the sensor's alerting behavior.

Photo Evidence: The photo set is moderately comprehensive but not fully complete. Photos TC_05725, TC_05726, TC_05727, TC_05728, TC_05732, TC_05733, TC_05734, TC_05735, TC_05736, TC_05737 provide multiple views of the nosebox wiring compartment with the multimeter consistently reading 13.5V across circuits, confirming voltage restoration after the 7-way replacement. Photos TC_05730 and TC_05731 document the old and replacement 7-way receptacles respectively. Photo TC_05715 shows the junction/distribution board inside the nosebox. Photos TC_05744, TC_05747, TC_05749, TC_05750 document trailer marker/clearance and turn lights. Photo TC_05874 shows the removed/replaced Grote strobe lights on the ground, and TC_05875 shows the rear of the trailer post-repair. The PCT TechAssist app screenshot (IMG_6229) shows all four monitored circuits (Red, Green, Yellow, Brown) marked as 'Verified' with 'Sensor Paired' and 'Maintenance Verified' status confirmed. However, no photos of the Grote strobe brake light illuminated and installed in its final position were provided, and not all individual brake circuit lights were photographed while illuminated, leaving a gap in full circuit documentation.

Vendor Compliance: The vendor (TA) demonstrated generally good compliance with the LCM troubleshooting procedure. The TechAssist app was clearly used — the screenshot (IMG_6229) confirms sensor pairing and maintenance verification with all circuits showing 'Verified.' The technician methodically tested all nosebox posts with a multimeter, identified the intermittent open on the brake circuit by wiggling the 7-way connector, replaced the receptacle, and then performed a full light walk-around. The technician's notes are detailed and transparent, including the parts sourcing challenge. The primary compliance gap is the absence of photos showing each brake circuit light individually illuminated and the Grote strobe installed and lit in its final position. The marker/clearance light replacement was also captured in the line items with supporting photos.

Repair Summary: Two primary repairs were completed on the RED (Brake) circuit: (1) R&R of the 7-way receptacle (part #16726, $35.99) which restored full 13.5V brake circuit continuity — labor billed at 0.5 hours ($121.98); and (2) replacement of the Grote rear strobe brake light ($160.64) which required special ordering through FleetPride due to non-stock status, with repairs completed 5/22/2026 as authorized. Additionally, one marker/clearance light was replaced (R&R labor $61.58). An Amazon PCT sensor activation line item appears on the work order, likely reflecting sensor re-pairing/verification after repairs. Shop supplies ($23.59) and a lot service hourly labor charge ($75.00) for parts sourcing were also included. All lighting parts appear to be appropriate OEM-equivalent replacements, and the Grote strobe is a recognized compliant brake circuit component.

Key Concerns: The parts sourcing delay (repair authorized 5/22, one day after initial inspection on 5/20) is notable but was handled transparently by the vendor with proper authorization. The extra $10/hour parts-run charge noted in the technician's notes does not appear as a distinct line item, which may warrant billing review. The PCT app screenshot shows 'No data' beside each circuit rather than actual live readings, which could indicate the app screenshot was taken prior to or independent of live circuit activation — reviewers should confirm the 'Verified' status reflects post-repair confirmation. The marker/clearance light replacement is a secondary finding not directly tied to the RED circuit alert but is a legitimate ancillary repair. Overall, this is a well-documented, properly diagnosed work order with no major red flags.