TM 10-3930-669-20 1.  DRIVE AXLE OVERHEATING (CONT). KNOWN INFO TEST OPTIONS Engine temperature 105°F or over. Glow plug indicator operates. Parking brake OK. Brake fluid OK. Drive axle oil level correct. Master cylinder OK. Drive axle OK. Drive axle oil cooler ground wire OK. Drive axle oil cooler OK. Relay R7 ground wire OK. Wire 29 to relay R7 OK. Wire 73 OK. Relay R7 OK. Wire  29  to  engine  temperature  switch OK. Engine temperature switch OK. Wire 71 OK. Axle oil pump ground wire OK. Axle oil pump OK. Relay R8 ground wire OK. Wire 29 to relay R8 OK. Wire 74 OK. Relay R8 OK. Wire   29   to   drive   axle   temperature switch OK. Voltage test. STE/ICE-R #89. POSSIBLE PROBLEMS REASON FOR QUESTION Drive     axle     oil     temperature     switch faulty. Wire 72 faulty. If  22  to  24  vdc  are  not  present, axle    oil    temperature    switch    is faulty.      If   axle   oil   temperature switch is OK, wire 72 is faulty. ¬ 2-376