Stupid Shorts! AC/heater fan this time...

[tribri1]

So the front AC/Heater fan works intermittently. Can't figure out any rhyme of reason, my lady says it only works when she is not in the van and she may be on to something.

Sometimes it works and sometimes it doesn't work. When it works, it works just fine. When it doesn't it work there is no fan at all. So it is not like a bad ground where it is intermittent. I checked the fuses because that's always the first thing I do. It acts like a breaker, but according to the diagrams I don't see any breakers. What am I missing?

[MountainManJoe]

all speeds or just the highest?

[tribri1]

All speeds, when it works it works fine, when it does not work there is nothing. I have turned it to off and left it there hoping something would reset, no luck... I was thinking it had something to do with the dash lights being on or not since my lady is typically in the van with me at night ;-), but I noticed today the dash lights were on nd the fans still did not work.

[astroturf]

I had a similar problem last winter. Not the time for it to break.
I first started out by tapping the blower motor housing... Bingo, It worked. For a time.
I tapped it so hard in hopes it would work one day, that I cracked the plastic cover.
No love. So off to the parts store I went. I bought a new blower motor.
Pulled the reservoir tanks, disconnected the blower motor, plugged the new one in. No love.
Fiddled around with the resistor wiring, Wah Lah. New blower worked.
Plugged in to the old blower motor, and it worked too.
I found the plague inside the resistor plug. It looks like this. (First Pic)
I was able to get by, simply by pulling up on that plugs wiring. Made it through the winter.
Come the Spring, I needed some AC, and she would not work.
Pulled the bottles, and could not unplug the wiring from the resistor.
The plug innards had melted and fused the halves together.
I finally got them apart, and headed off to the Junk Yard. They were toast.
Both the wiring, Plug, and Resistor would have to be replaced.
2 wiring looms were pulled from the JY, as well as 2 resistors, and a blower.
I cut in a new loom, plugged in one of the used resistors, and never did need the blower.
I have in storage, 1 wiring loom, 1 used resistor, and 1 used blower.
It has been working Okie Dokie so far. I will inspect it this Spring, to determine whether or not it is happening again.
As a side note... After I made the repair, I began turning off the all of the Heater Controls when turning off the van.

Long winded, I know.

Hope it helps, Jim

Heater Resistor Plug.jpg

[tribri1]

Long winded but brilliant if it works... I guess I do have a back story, I went rafting a few weeks back (yes rafting, in Oregon in January...) and one of the girls (yes, we even convinced girls that it would be fun) on the trip came out pretty cold by the end. She sat in the front seat with the heat and fan on high for at least 20 minutes if not longer... It has not worked the same since. Could be the problem, thanks for giving me a place to start looking.

[LiftedAWDAstro]

To test if it's the motor or resistor pack/wiring, when it stops, unplug the connector at the motor and see if you have 12+ volts if the fan speed is on high. I had a motor with a loose connection inside that would quit when you needed it most! Just tapping on it with my fist would make it work. Swapped in a new motor and it was good.

PS running the fan on high for 20 minutes had nothing to do with it failing. I run mine on high speed almost all the time in the winter. With the snowshoeing we do, everything is wet when we get ready to go home and the extra body heat we give off fogs the van up fast so I run the defroster on high speed to keep the windows clear. I just adjust the temperature setting to be comfortable.

[astroturf]

Any closure on this?

Thanks, Jim

[tribri1]

Sorta, I have not had a chance to dig in and check it out. Then it started working fine again. I'll still check all the connections, but unless there is something obvious it will be tough to find a short that is not shorting. I'll keep all you posted...