Damaged insulation of the wire unit of the temperature sensor (reference 1 image "Light pipe temperature sensor connection") which measures the temperature of thecooling block of the light pipe entrance. When disconnecting the wire unit of the temperature sensor from the Signal backplane, the error code is changed to “light pipe - temperature sensor open 5964”.

1. Repair the insulation of the wire unit using shrink sleeve.

2. If not repairable, replace the whole wire unit and temperature sensor.

Defect temperature sensor on the cooling block of the light pipe entrance. When disconnecting the wire unit (reference 1 image "Light pipe temperature sensor connection") of the temperature sensor from the Signal backplane, the error code is changed to “light pipe - temperature sensor open 5964”.

Replace the temperature sensor.