QuestionThe front A/C blower for my 2001 T&C stopped operating recently after a two month period of suddenly stopping (usually during or after a heavy Florida rainfall, but sometimes it would not fail during a rain); it worked fine otherwise. Ihad also just replaced the front brake pads with no problems. Switching the blower relay dosen't help and the 40A fuse is good. Any thoughts?
Thanks
AnswerHi Norm,
While I only have wiring diagrams covering thru '99, I suspect that the blower motor circuit is the same in your '01.
The blower relay needs a 12V supply to the actuator coil in order to close the relay switch. That is supplied by fuse #12, a 10 amp fuse in the junction block in the cabin. It appears that fuse gets its 12V from the ignition switch and so when that switch is in the run position the fan relay should be closed and passing 12V from the 40 amp fuse to the blower motor. I would familiarize myself with the sound or the feel of the relay at the moment when the ignition switch is turned to run, so that when the blower next quits you could verify that the relay is closing by checking for the sound or the touch of that relay while a helper turns the ignition switch to run. If it clicks then that part of the circuit is o.k. and you should find 12V to be present at the dark blue wire of the blower motor.
If you don't get 12V at the blower, then there is something wrong in the wire from the relay to the blower motor. If it doesn't click then either the fuse #12 is unreliable in its contacts or it isn't getting 12V from the ignition switch, so you could check the clips at the fuse to see which is the case.
If the blower is getting the 12V and yet it doesn't work, then either the blower motor resistor block or the control switch is bad. When the resistor block (which I believe is located in the intake air duct, and which you may well find in the engine compartment at the far upper outside corner of the firewall on the passenger side with the plug on the engine side of the wall and the resitors on the other side in what is at the point the air intake duct) fails, the effect is rather to have the fan only run at high speed rather than not at all. So if you don't have that behavior, I would check the control switch in the heater control panel for continuity in the various positions it can assume.
I wish I had a single certain answer for you, but unfortunately it is a circuit with several switches (ignition, blower relay, control panel), the resistor block, and two fuses that have to be all working properly. One thing you might want to do is look very carefully at the 40 and the 10 amp fuses to see if their central conducting wire might be cracked/weakened due to heating and cooling and thus failing when it gets warm, only to spontaneously reconnect when it cools. This can happen with fuses as they age.
Please let me know what you find and how you fixed it.
Roland
