Windshield Wipers

[JacobsD]

Hey guys, I saw the little bit in the most recent issue of TDR about windshield wipers and it reminded me about mine. On my 05, it will wipe about 3 times on delay, then stop for the normal delay. Also sometimes it will not work at all on the delay, but if I switch it to just normal wipe it will work, but when I turn it off it stops the wipers right where they are at the moment. Very annoying #@$%!



I had the dealer replace the multi-function switch under warranty, but it still does it. What are the odds of getting a defective switch? There is no delay box or anything is there? Maybe the motor itself is bad?



Thanks in advance

 

[rbattelle]

Wow, that's potentially a tough one to diagnose, especially if you've got a Totally Integrated Power Module on the truck as opposed to a traditional wiring scheme.

It might be a problem within the wiper motor itself. Here's some relevant text from the 2006 manual:

The wiper module operation is controlled by the battery current inputs received by the wiper motor through the wiper on/off and wiper high/low relays. The wiper motor speed is controlled by current flow to either the low speed or the high speed set of brushes. The park switch is a single pole, single throw, momentary switch within the wiper motor that is mechanically actuated by the wiper motor transmission components. The park switch alternately opens and closes the wiper park switch sense circuit to ground, depending upon the position of the wipers on the glass. This feature allows the motor to complete its current wipe cycle after the wiper system has been turned Off, and to park the wiper blades in the lowest portion of the wipe pattern. The automatic resetting circuit breaker protects the motor
from overloads.

Your symptoms sure sound like a bad park switch, although that doesn't explain the other odd behavior you're noticing. The manual isn't clear on how much "intelligence" is built into the motor circuitry and how much is organic to the vehicle control system. If the vehicle is merely telling the motor "go into delay mode X", and the motor "knows" what to do from there, then a motor replacement will fix your problems. But if the vehicle itself is telling the motor "wipe now..... now..... now... . etc", then a motor replacement isn't likely to cure the problem.

How much is a new motor?

Ryan

 

[Matt400]

My son just bought an 04 thats doing this so I am doing some looking and found your post. His trouble is the delay portion- his will wipe 2 or 3 swipes then do the normal delay for a while then its 2 or maybe 3 swipes at a time, pretty odd.

Did you ever get yours fixed Dave?

 

[Grumpytrkr]

My 04. 5 was doing the same thing. On 10-21-06, (42,332 miles) the dealer replace the Wiper Motor Module, under warrenty. This fixed the problem.

 

[Matt400]

the dealer replace the Wiper Motor Module, under warrenty. This fixed the problem.

Hrmm, I didn't know there was a separate one. Thought it was integrated with the FCM? or maybe what your dealer replaced was the wiper assembly also referred to as the wiper module that consists of the motor & arms.

Testing for this trouble is a bit confusing, I read in the service manual-

The FCM controls wiper motor operation

by controlling a ground path through this circuit

Correct me if I am wrong anyone but it appears the wiper switch just requests wiper operation and that request is carried out by the FCM which controls the high and low speed relays in the ICM.

I am guessing the delay function is part of the FCM and not the switch itself? I don't find this info in the service manual.



If the wipers did not park correctly I would suspect the wiper motor but on this one they swipe several times and then will delay properly until several swipes are made again. I am thinking either the switch is bad and the FCM is not recognizing the setting or the FCM is bad. I just hate replacing a part to see if that is the trouble.

 

[Matt400]

Wow... was just researching some more on this and find the instrument cluster is involved too.

In delay mode the multi-function switch sends the request to the instrument cluster which sends that request to the FCM.

I learned the FCM calculates the length of time however my Son's truck wipe times are ok when they do delay, they just wipe consecutively for 2-3 wipes then delay.



The switch provides resistor multiplexed inputs to the instrument cluster. This makes me think its possible steady low speed and delay operation could be sent from the switch at the same time.



Guess we will have to try a switch cuz the other 2 components- Instrument cluster & FCM are very expensive. The Wiper Module (motor assembly) am pretty sure is good, its just doing what its told to do.

 

[Grumpytrkr]

Hrmm, I didn't know there was a separate one. Thought it was integrated with the FCM? or maybe what your dealer replaced was the wiper assembly also referred to as the wiper module that consists of the motor & arms.

Don't know. Vehicle was under warranty. Handed the dealer the keys, they handed me the keys to the salesman demo, and when I returned, the truck was fixed.

 

[hearingyourlies]

Andres ... how did you solve your problem?

 

[sag2]

Wow... was just researching some more on this and find the instrument cluster is involved too.

In delay mode the multi-function switch sends the request to the instrument cluster which sends that request to the FCM.

I learned the FCM calculates the length of time however my Son's truck wipe times are ok when they do delay, they just wipe consecutively for 2-3 wipes then delay.



The switch provides resistor multiplexed inputs to the instrument cluster. This makes me think its possible steady low speed and delay operation could be sent from the switch at the same time.



Guess we will have to try a switch cuz the other 2 components- Instrument cluster & FCM are very expensive. The Wiper Module (motor assembly) am pretty sure is good, its just doing what its told to do.

Before you replace a switch, is it in delay only that it makes multiple swipes and then delays normally again, instead of delay, swipe, delay, swipe etc?

If it is, the park switch or the ground may be bad on the motor. When the wipers park, do they park in the same spot, and do they park quickly, in other words does it look like the motor stalls in the park position to keep from overshooting the park position? Compare your truck operation to your son's truck, paying close attention to how quickly they stop.

If it looks like they might be overshooting hold some resistance on the wiper arm (to stall it at the park position) and see if it acts normally.

 

[Matt400]

Before you replace a switch, is it in delay only that it makes multiple swipes and then delays normally again, instead of delay, swipe, delay, swipe etc?

If it is, the park switch or the ground may be bad on the motor. When the wipers park, do they park in the same spot, and do they park quickly, in other words does it look like the motor stalls in the park position to keep from overshooting the park position? Compare your truck operation to your son's truck, paying close attention to how quickly they stop.

If it looks like they might be overshooting hold some resistance on the wiper arm (to stall it at the park position) and see if it acts normally.

Somehow I missed your post on this, I did change out the switch and we thought it was ok but guess not because the trouble is so intermittent as its doing it again. It has the trouble while in delay mode only, slow and fast work good. Something new since we changed the switch that he had not seen before is the wipers stop in the middle of the windshield when he shut them off. He flipped them on/off again and they parked correctly. Knowing this and what you said above sounds like a bad motor.



Another odd thing he has seen is the wiper take a swipe when he gets in the truck but before he puts the key in the ign, pretty weird. . just one swipe and he has seen that twice, I questioned him on this and its possible the truck was previously shut off in the "intermittent" mode.



I compared with mine and they park in the same manner, the trouble is so intermittent I have never seen it.

Thanks for the info!

 

[PBJ2500CTD]

I place a bet on the wiper motor assembly - it sounds like the return to park circuit/switch is not making good contact. If that circuit doesn't work properly the wipers will not return to park and will not activate the intermittent cycling.