AC blower stops on long trip

[JBotz]

just got back from 5000 plus mile trip. after driving 5 to 600 miles the ac blower stops blowing. turn it off for 10 or so minutes and then it will work for awhile then stop again. any one have this prolbem? i need some help. Thanks, Jim.

 

[kenny61]

freezing up ?

 

[JBotz]

nope thats what I checked first.

 

[kenny61]

over heating cicuit breaker? Not sure how these new fangled ones are wired... .

 

[DZink24]

https://www.turbodieselregister.com...2-poor-hvac-air-movement-plenty-cold-air.html

 

[rbattelle]

Sounds exactly like the symptoms of a freezing evaporator.

Ryan

 

[JBotz]

yes lots of cold air when going 75 down road.

 

[JBotz]

pulled blower motor out and blew out all ducts with air compressor. got a lot of dust and dirt. but still does it after 5 or so hours of driving. have 2 check the power wires when I get it to stop blowing again

 

[sag2]

The blower motor is powered by blower motor relay in the IPM, and grounded by the control head via the blower motor resistor. I don't see anything in the circuit that would be affected by time powered up.

When it happens does the blower make any noise? Does it run on one speed but not the other? If you turn off the A/C button for a couple of minutes and then turn it back on does it make a difference? How about if you cycle the key?

 

[JBotz]

the motor just stops. no noise. when you turn off the fan switch the light on a/c button stay's on till you turn the a/c button off. it's like some thing is feeding back through sysetm.

 

[Adventure Bob]

Just got mine fixed... The clutch on the Sanden compressor was trashed, but not completely. It would spin everything till it got hot and then it would shut the compressor down. The air output would start to go to a trickle and then would stop damn near all together. When the tech showed me the clutch I was flabergasted. He said the sanden isnt really a great choice for diesels due to the vibes. Not sure if thatll help but it fixed mine, you can hang meat in the cab now.

 

[JBotz]

will check that out to day. thanks for the heads up.

 

[JBotz]

Well the clutch looks ok. will have 2 wait till I go on long trip 2 see if it cuts out again. running around town it will not do it.

 

[SquareDave]

Was this blower motor problem ever resolved? I have this same problem now in 2016. The blower motor may or may not work immediately upon startup, but has always eventually started within a few minutes and will work fine while driving locally (for the most part). On a long trip it starts exhibiting the same symptoms that JBotz had. I did the easiest thing myself which was to replace the blower motor resister - didn't work.

In my online research I have run across solutions such as: (1) ignition switch terminals scorched - replace ignition switch and (2) A/C-Heater switch panel needs replacing. Has anyone tried one or both of these?

Thanks

Dave
2006 Dodge Ram 2500 ST (approaching 200,000 miles on the way to a million)

 

[SquareDave]

Apparently, this will have to wait. The shop quickly checked the voltage, and they were within specs. Since they couldn't replicate the problem, they went on to do the brake job. The good news is that I haven't been able to replicate the problem either. Over the past 10 days, the blower hasn't missed a beat - no delayed starts, no slowdowns, no stopping, whether I'm driving 10 miles or 110. That's good because it has been in the nineties here with forecasts of 100°+ in the next few days. The service writer seems just as mystified as I am.

 

[SquareDave]

The blower motor problem reared its ugly head. I replaced the blower motor - problem solved.

Undid 3 screws and a connector to remove - put in new motor and put screws and connector back. Easy job for an amateur.