Dash fans not working for the a/c

[CyberVet65]

I am on the road headed East. I am using the dash a/c to keep comfortable. I do use the gen set when stopped to run the coach a/c.
Pulled into Wal-Mart to do some grocery shopping and when I turned the ignition on I have no dash fan to move air. I followed it down to a 15 amp circuit breaker. It is the same one as the slideout uses. I swapped them and the slide goes out. But I still have no fan on the dash a/c.
The unit is a 1999 HR Endeavor on a Freightliner chassis. I have checked the fuses and breakers for the chassis and then I checked the fuses for the house. Nothing blown. Any suggestions? It is going to be a hot one if I don't get this fixed.
Thanks

[HarveyP]

I just replaced the one on our 94. The fan on mine is in front of the passenger's feet. I pulled the old one and took it to a Napa store, got an exact replacement for just under $20. Good luck, HarveyP

[jww]

If you have confirmed power to the switch i would suspect the blower motor resistor. It should be located in the air plenum, two screws attaching it to the plenum with one electrical plug attached. On our Dip. it is located on the passenger side, up high on the outside of the front firewall. Mine is Motocraft part. Take the original to a Ford Dealer and they can match it. Easy component to replace.
Good luck

[wa8yxm]

Well, the dash blower in my coach shows signs of bad bearings (I need to chat with Workhorse about that too) however my car is perhaps a better training ground

It has the same problem

First FIND the blower (on a Workhorse gasser it may be over your partner's right foot,Ford put it there on the Mercury Tracer (And ford Escort) too)

Check the connections. both on my Chevy Lumina (Where it's elsewhere) and my Wife's Tracer the connection at the motor failed.

Then on to the speed control resistor array This will be a flat panel that sticks into the air flow somewhere, often near the motor. Check the connections here. This array is present on all speeds except HIGH

Now depending on your system you may have a pair of relays, High and low speed (high speed bypasses the array)

And finally.... There is the control switch and motor themselves.. If you can identify the motor and match the connectors you can feed it 12vdc direct via a proper fuse or breaker

[nbounder]

My old Chevy had a wire coil resistor crimped onto a board that sat in the airflow. Then, after a number if failures of the crimps, etc, they actually put a real relay in the HI fan circuit, which helped a lot. I don't know which configuration your rig has, I bet the mfr knows - try a call to tech support!

[bjsheldon]

Originally Posted by jww

If you have confirmed power to the switch i would suspect the blower motor resistor. It should be located in the air plenum, two screws attaching it to the plenum with one electrical plug attached. On our Dip. it is located on the passenger side, up high on the outside of the front firewall. Mine is Motocraft part. Take the original to a Ford Dealer and they can match it. Easy component to replace.
Good luck

My dash blower only works on high speed. Could this resistor cause this problem also?
Winnebago Adveturer on Ford chasis with V-10 gas.

[bjsheldon]

My dash blower only works on high speed. Could this resistor cause this problem also?
Winnebago Adveturer on Ford chasis with V-10 gas. OK I change the resistor pack and no help; still only runs at high speed. What next?
John

[garym114]

Don't know what year your rig is but it is probably an evans system. The link is to their troubleshooting guide.
Evans Tempcon, Inc

[bjsheldon]

I have a 1999 Winebago. I went to the Tempco site and found what looks exactly like mine. After not being able to figure out anything because they didn't address my specific problem . I called Tempco and was told by a recording that they coundn't help a private coach owner. I measured voltage at the blower motor and get 12 v at any switch setting. I checked voltage at the resistor connector and get 12v at 1 terminal all the time, 12v at 2 terminals at #3, 12v at 3 teminals at #2, but no votage at the 4th terminal at any position. Any more suggestions?
Thanks
John

[ernieh]

Originally Posted by bjsheldon

My dash blower only works on high speed. Could this resistor cause this problem also?
Winnebago Adveturer on Ford chasis with V-10 gas. OK I change the resistor pack and no help; still only runs at high speed. What next?
John

Not sure how your MH is wired, but many vehicles I have worked on in the past have two sources of power to the blower. On high, the power came directly from the battery via a terminal on the alternator. The power for the slower speeds, thru the resistor, came from another fuse in the fuse panel. The fan speed switch was actually on the ground side of the blower.

Don't know if this helps or not.

Good luck.

[wa8yxm]

There is another thread on "Fan only works on High" I know the GM system, since I do not drive fords (If I can help it) I don't know the ford system

On the GM system (Also Workhorse) there are a pair of relays called the "High Speed Relay" and the "Low speed relay"

Now when you turn the fan on the low speed relay engages, this feeds power to the non-motor end of the resistor pack, The fan switch may short out part of that resistor pack. for medium or medium lo/hi depending on the number of fan speeds you have.

When you switch to HIGH, the high speed relay engages and feeds power direct to the motor.

If the low speed relay is not working.. you have only high, no other

The switch, is also a supect

ANd a few wires.. You may also have two fuses (low and high) but that , I doubt.

NOTE: this is true for GM.. May or may not be the case with Ford.

[bjsheldon]

Thanks for all the suggestions. It was the fan relay on the blower housing. Everything works fine now.
John

[CyberVet65]

Fixed! Bad fan motor.