2003 Chrysler Town and Country Van came in with the complaint of the blower operates on high speed with key on and cannot be adjusted down. This procedure will also apply to Dodge Caravans with auto a/c. The controls and indicators seemed to work normally. I checked the wiring diagram and component locator and found that the blower power module is located behind the glove box. Good place to start.
After opening the glove box there are two stops the have to be depressed inward in order to drop the box down.
The blower power module is directly behind the lowered glove box. It is held in place by two 8mm hex head screws.
After removing the two attaching screws, the blower power module can be positioned for testing.
Turn the key on and while manually rotating the blower switch from low to high you should see a voltage change between about 2 volts (high)up to about 10 volts (low) on the blue/light blue wire. It is the middle wire in the left connector pictured below. Because the blower was working on high speed there was no need to do any other testing, however if you were to have low blower or no blower you would need to test further. Check for 12 volts – on the black/orange wire and 12 volts+ on the dark blue wire in the three wire connector. If either is missing check respective fuse and ground connections. Next check for 12 volts between the blue wire and the dark blue /yellow (sometimes black as pictured below) wire in the two wire connector to the right of the pictures. If either signal is missing in the two wire connector and the three wire connector tested good then the power module is faulty. If 12 volts power and ground are present then the blower motor is faulty. Usually bumping the motor with the key on and the blower switch on high will make the motor work for a little while because it will reset the worn brushes.
Three wire connector:
Black/Orange wire should have a constant ground.
Dark Blue wire should have 12 volt switched power from the front blower relay. The front blower relay is located in the Integrated Power Module (underhood fuse box).
Blue/Light Blue wire should have a varying voltage from about 2 volts(high blower command) and a nominal 10 volts(low blower command).
Two wire connector:
Check for a nominal battery voltage reading across the two wires. Key on and blower set to high.
I removed the mounting screws to gain better access to the wiring for testing.
Be careful to keep the aluminum cooling fins away from the metal brace for the glove box. It will complete the ground circuit for the blower motor and will scare you when it sparks.
Place an insulating cloth between the aluminum fins and the brace if you want.
A good look at the blower power module.
Installed the new blower power module and all is well.
Sparky – apologize for the two similar entries, I am Ed and registered in Google as Stumpy 78. After I wrote the first one, I did not see the comment on top of the page that the question was sent to you for approval. I’ll bring a multimeter to work tomorrow to check the voltage. I leave the van at a train station close to work. Really appreciate your help!
With all harnesses connected and the key on check for voltage from chassis ground to black/orange wire. If voltage is indicated there will be a faulty ground supply to the black/orange wire. If it is okay the new module is faulty.
Sparky, 2001 Town & Country with Auto Temp Control – front blower not working at all. Voltages on 3 pin connector: black/orange to dark blue – 11.4 v. light blue to black/orange 2.5v to 8.7v. 2 pin connector: black to green 2.2v. I tried chassis ground to black – 11.9v, and to green 12v. I replaced the control module and it still does not work. I disconnected the 2 pin connector and ran power from a separate 12v battery to the blower motor and it runs. What did I miss?
2001 T&C with auto temp control. Front blower not working. 3 pin connector checked out. blk/orange to dark blue – 11.4v. blk/orange to light blue -2.5 to 8.7v. 2 pin connector – green to black 2.2v. chassis ground to black 11.9v; to green 12v. hooked the 2 pin connector to separate 12v battery and fan worked. I replaced the power module and fan still does not work. Could it be a bad new module? Thanks
The low voltage condition could have made the module or control head react to keep the blower motor inoperative. The battery may have went dead due to the key being on and the doors open for an extended period of time. Also the glove box light may have been on from the time the glove box was removed. In either case I am happy that your new part is okay. I do recommend having the battery tested as cold weather is on it’s way.