F53 & Workhorse Chassis Wiper controller issue

[94-Newmar]

Customer unit today here for repair.... This particular coach is a 2010 Allegro Open Road on a Ford Chassis, but according to Tiffin, this same issue can apply to the Workhorse chassis as well - this could be applicable to any F53 or Workhorse chassis used by any Coach builder as well...

Customer started coach and while sitting there idling the wiper controller caught fire. Fortunately able to put it out quickly. He was VERY lucky he didn't simply start it and walk away.

Chasing wires down I find that there is only 1 fuse feeding this controller, a 30amp from the Ford chassis panel. Obviously, 30 amp is far too much for wiring of this size. I have not determined if the wiper motor is locked up due to ice and snow on the windshield, but nonetheless, this should not happen - it should have simply blown a fuse.

Also attached is page 24 of the Ford Body Builders layout book for this chassis. I have circled in blue the relevant paragraph stating that there is a 30amp fuse and that the controller is not protected any further.

I called Tiffin, and as always Tiffin customer/dealer/repair support was 110%. They are aware of this and had issued a notice (SB-17) about it back in 2007. In either the Workhorse or F53 chassis, the fuse must be changed. In the Ford fuse panel on the drivers side replace the 30amp fuse in position #11 with a 15amp (MIN15) and on the workhorse chassis, on the drivers side fuse panel change the 30amp fuse located in position #22 with a Cooper Bussman #212-15-00 Series 21X mini circuit breaker.

If you have an F53 or Workhorse Chassis, might I suggest you double check the fuse values for the wiper controller.

I will update the thread after I check the wiring further and ensure the wiper motor isn't locked - trying to find out what caused this in the first place.

[Excell]

There is supposed to be a circuit breaker in the wiper motor .Maybe the motor was replaced with one that doesn't have one .

[94-Newmar]

Perhaps.. I haven't got a chance to get back to this one yet. Even if the unit is fused between the motor and controller there still should have been something less than 30amp protection from the panel to the controller - as described in the Tiffin service bulletin above.