12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

AC won't change speeds! Why?

Old Apr 15, 2012 | 01:47 PM
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Default AC won't change speeds! Why?

My brothers '95 dodge dually has an excellent ac system that blows ice cold eveery time. But one time it sat without moving for 2 months due to a bad starter. After the starter was replaced, it ran great and still does, but the ac will only come on if you turn it to full blast. Same withe heater. What is causing this?
 
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Old Apr 15, 2012 | 01:59 PM
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The switch is bad. The switch that goes hi to lo..
 
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Old Apr 15, 2012 | 04:53 PM
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I forgot to mention that it did not start doing this until after it sat for 2 months. What caused it to quit after sitting for that long? Also, how much is the part and is it something me and him could do?
 
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Old Apr 15, 2012 | 05:16 PM
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It's usually the resistor pack for the blower motor, not the switch.
 
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Old Apr 15, 2012 | 05:23 PM
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Ditto on the resistor pack
 
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Old Apr 15, 2012 | 08:53 PM
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Guess I havent messed with the dash crap that much. Where is this resistor pack?
 
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Old Apr 15, 2012 | 09:27 PM
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Might have got some critters up in the ventilation system, be sure to clean out any debris that may be in there. Or it may just be corrosion.

---AutoMerged DoublePost---

Check your local parts stores, they should be able to tell you where the resistor pack is located, possibly supply a service manual for a reasonable price. Quicker to look in a book for basic information than post on the internet and hope someone who knows the answer responds in a timely manner. Course the forum is good for less basic info.
 

Last edited by Eddiebuntain; Apr 15, 2012 at 09:27 PM. Reason: Automerged Doublepost
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Old Apr 15, 2012 | 09:30 PM
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Should be sticking out of the heater box, around the glove box area.

Sent from my Motorola Electrify using Tapatalk 2
 
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Old Apr 17, 2012 | 12:07 PM
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Sounds like a blower motor resistor to me as well
 
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Old Apr 20, 2012 | 09:12 PM
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Thanks everyone!
 
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