After extended idling, the high-speed cooling fan relay may fail in some of the affected vehicles

Bulletin number

21B05

Component

Engine and engine cooling

Summary

After extended idling, the high-speed cooling fan relay may fail in some of the affected vehicles. A failure will cause the fan to either continuously run or never turn on. A continuously running fan will increase the temperature of the relay’s connections (terminals) to beyond their design maximum. This may eventually create an electrical arc which heats and damages the relay terminals. Customers may experience a drained battery and a non-functional or even a melted/burned high-speed cooling fan relay inside the battery junction box (BJB). A damaged non-functional relay causing the fan to never turn on, may lead to engine overheating at idle.

Owners of these vehicles have filed 4 complaints in the engine category.