I was doing a little research into your wiper system wiring diagram, and I must tell you, it's a lot more complicated than it should be. (Probably why American car manufacturers are dieing out)
Instead of me trying to put this in my own words, here's the data straight from the manufacturers mouth: All the front wiper and washer system operation is controlled by the FCM (front control module) logic circuits, and that logic will only allow these systems to operate when the ignition switch is in the Accessory or On positions. Battery current is directed from a B(+) fuse in the Integrated Power Module (IPM) to the wiper on/off relay and the wiper high/low relay in the PDC through a fused B(+) circuit. The FCM uses low side drivers to control wiper system operation by energizing or de-energizing the wiper high/low and wiper on/off relays. The FCM uses both high side and low side drivers to control the operation of the washer pump/motor unit. The multi-function switch circuitry receives a clean ground output from the SCCM (steering column control module) on a multi-function switch return circuit, then provides resistor multiplexed inputs to the SCCM on an intermittent wipe mux circuit to indicate the selected wiper system mode and on a wash/beam select mux circuit to indicate the selected washer system mode.
As you can see, Chrysler was too " Smart" just to put an " On/Off" switch in the wiper circuit and make it easy. But what I think is happening is, there's either a bad " ON/OFF" relay, the Front control module is defective, or there's a short in the wiring between the FCM and the wiper motor.
You'll need to break out the DVOM (or test light) and start probing the entire circuit from the wiper motor to the module and to ground. Where ever you have a " ground" and shouldn't, then that's your short.
But keep in mind, I'm not exactly sure about this issue. I'm just giving you my educated guess. It's pretty hard for me to give you any accurate information without having the electrical diagram in fromt of me while actually looking at your system.
Sorry, but good luck.
Wednesday, March 17th, 2010 AT 11:30 PM