Trinary switch location

[Steven Link]

Does anyone know where the switch/relay/ or fuse to the condenser fan is located on a 2009 Marquis. My AC guy is having a hard time locating it. Called Ken at BCS and he was some help but still unable to find the fan control. Fan was bad...replaced that but now no power when the compressor is activated. Cooling works but fan does not come on. It should be on the firewall or near the evaporator core...but we are having no luck finding a fuse or relay. Any help would be appreciated.

Steven Link

[Joel Ashley]

Both the relay and the circuit breaker for my Monterey's condenser fan are in the electrical bay, Steven.  I would expect the same for your Marquis.  Not that they'll be in the same positions, but my relay is #K3, and the breaker is CB12, in case it gives your tech any guidance.

Joel

[Steven Link]

Thanks Joel, two fuses in the electrical bay but no marked relay. Both fuses check out ok. Monaco has been no help... in fact one tech thought the evaporator/condenser coil was on the radiator   I knew I was in trouble when Monaco closed one month after we took delivery on this coach. Guess the chickens are coming home to roost! may just have to run a whole new circuit off the compressor.


Steven

[Dan Stussi]

Now my MH is a 1998 Monterey so it may not apply. My Trinary switch is right inline with the low pressure fill valve. The switch works on both temp and pressure. Mine went bad sometime this spring. i bought one, then chickened out installing it as I was afraid I might twist the tubing trying to loosen the trinary switch. So I added a relay between the AC switch and the condenser fan and it powers on anytime the AC is switched on. That is how they used to work and there is not question whether it is on or not. The low pressure cutoff on the old Trinary is still in place so if I loose R134 it will still shut down.

All of the above is at the front of my MH. The valves and switches are on the firewall on the cap side. I just stood in there and worked on it.

Dan

[Steven Link]

Thanks everyone for your input. We finally found it from the wiring diagram (and an educated guess) I was sent before the Beaver factory closed in Oregon. Turns out the fuse to the condenser fan is located in the ceiling of the front full bay...not in the electrical bay. Found it after removing the ceiling panel. The binary switch (not trinary as I said before) is on the evaporator on the firewall. So bad fuse replaced and new condenser fan installed and everything is great. Just hope the high side pressure has not damaged the compressor. I have a habit of turning the ac off if idling for a long period. That may have saved my compressor. Seems that the later models run the condenser fan circuit thru the chassis multiplex

Steven Link