Engine wiring harness insulation degrades, shorts
ELECTRICAL SYSTEM, ENGINE
3 NHTSA complaints · 2025-04 → 2026-05
“The engine wiring harness insulation near the ignition coil connectors prematurely deteriorated due to prolonged exposure to engine heat in the turbocharger/exhaust area. Multiple wiring connectors exhibited brittle, cracked insulation with exposed conductors. The degraded”
“The vehicle is experiencing deterioration of the main engine wiring harness insulation, resulting in exposed wires contacting each other. This condition has caused intermittent check engine lights and electrical fault codes. The dealership has confirmed that the wiring”
“I am writing to escalate an unresolved service issue with my 2020 Mercedes Benz GLS 450, VIN [XXX] . During a maintenance service on March 6, my trusted independent services shop for 25 years, Carrera Motors in San Mateo CA, identified that the electrical harness of my GLS 450”