Wipers quit

[jotis]

02' liberty sport.
Wipers quit working periodically, usually after it has been raining for a little bit. I replaced the multi function switch and it worked great until the first rain. I have not trouble shot this when it wasnt working, ie power to the fuse with switch on because Who wants to work in the rain...Any ideas?

 

[Porkchop]

Maybe spray with garden hose till it stops then Check you can do this on a sunny day.

 

[Billwill]

Here is the circuit diagram for the 2002 KJ.

The fact that the problem happens when it rains would suggest that the problem lies under the hood...probably right at the wiper motor itself.

As suggested, hose down the area to see if it fails; I would start at the motor itself then work back over the various connectors ie. connector on the wiper and C100.

I also would check the ground point G111.

Circuit breaker No. 3 mounted on the Junction Block may be failing although that would tend to be a solid problem.

Swap the two relays around, re-plug connectors C2 and C3 and JB on the BCM.:shrug:

 

[jotis]

Thanks for the diagrams and the advice. I will do some checking and let you know what I find.

 

[jotis]

Ok, was able to do some work last week. Tried the water hose thing a couple of times and couldnt get the wipers to stop. So, I figured the water was coincidental cause that was the only time you really check 'em anyway. Over the weekend tried them a couple of times and finally tried them and they were not working. So, I started checking everything for power, found power all the way to the relay( during check out I swapped relays and re-plugged some connectors). Accessed the motor (major pita)and found(via ohm meter) what appeared to my "shade tree electrical/mechanical knowledge" a short in the motor. turned the motor manually and reattached the power and wipers worked. I figured this was probably a bad brush or something in the motor. Removed the motor and disassembled. Pulled brushes, they looked okay so I sanded them flat, the stator looked a little glazed so I sanded the stator and cleaned grooves. The grooves "widened" after cleaning. Put it all back together and it is working. I suppose I will have to use for awhile to see if that was the actual problem.

 

[Billwill]

Ok, was able to do some work last week. Tried the water hose thing a couple of times and couldnt get the wipers to stop. So, I figured the water was coincidental cause that was the only time you really check 'em anyway. Over the weekend tried them a couple of times and finally tried them and they were not working. So, I started checking everything for power, found power all the way to the relay( during check out I swapped relays and re-plugged some connectors). Accessed the motor (major pita)and found(via ohm meter) what appeared to my "shade tree electrical/mechanical knowledge" a short in the motor. turned the motor manually and reattached the power and wipers worked. I figured this was probably a bad brush or something in the motor. Removed the motor and disassembled. Pulled brushes, they looked okay so I sanded them flat, the stator looked a little glazed so I sanded the stator and cleaned grooves. The grooves "widened" after cleaning. Put it all back together and it is working. I suppose I will have to use for awhile to see if that was the actual problem.

There is a good chance that it will work OK now...time will tell.
There was probably a dirty spot on the rotor that you have now cleaned off.
There is always the possibility that if the motor stops in a certain position where there is a bad section of winding in the rotor then it will not start again.

 

[jotis]

The wife tells me they quit again last night. Probably not worth messing with if the winding has a fault. Good source for "cheap" liberty wiper motors?

 

[jotis]

Update,
I have tested this thing every which way but loose, and have come to the conclusion that I replaced good parts. i.e. motor and switch. I can jumper power at the relay and get things to work, continuity is where it should be. The only thing I can think of is the bcm is faulty. Gonna try a salvage unit and see what happens. The strangest thing while testing with a volt meter, I could get a 12v reading at the plug for the motor but if using a tester with a light bulb it would not light the bulb. Had me scratching my head for quite a while.

 

[rockymountain]

Update,
I have tested this thing every which way but loose, and have come to the conclusion that I replaced good parts. i.e. motor and switch. I can jumper power at the relay and get things to work, continuity is where it should be. The only thing I can think of is the bcm is faulty. Gonna try a salvage unit and see what happens. The strangest thing while testing with a volt meter, I could get a 12v reading at the plug for the motor but if using a tester with a light bulb it would not light the bulb. Had me scratching my head for quite a while.

Is the connector that connects to the motor ok? is it corroded or something? Whatever you bypassed with the jumper needs to be checked.