Windshield wiper/washer switch

[PbFut]

Can someone confirm functionality of the blue wire/middle pin on the wiper switch. My understanding is that this is the pin that grounds the pump mechanism for fluid to flow. My pump will not work. Wiper motor and wipers function normally in high and low position. Pressing the knob, I can hear a contact click, but the dark blue wire pin does not connect to the black wire pin as I suspect it should. The blue pin will not connect to either pin nor switch case when I depress switch the shaft. I believe the switch is my problem but want to make sure I'm not missing something.

[LockDoc]

Originally Posted by PbFut

Can someone confirm functionality of the blue wire/middle pin on the wiper switch. My understanding is that this is the pin that grounds the pump mechanism for fluid to flow. My pump will not work. Wiper motor and wipers function normally in high and low position. Pressing the knob, I can hear a contact click, but the dark blue wire pin does not connect to the black wire pin as I suspect it should. The blue pin will not connect to either pin nor switch case when I depress switch the shaft. I believe the switch is my problem but want to make sure I'm not missing something.

Yes, the middle blue wire grounds the washer pump. The wiper motor has to be running on low speed before the pump will work. That is what drives the actual pump. That is why pushing the center button on the knob not only energizes the the coil for the pump but also turns the wiper motor on low speed.

Don't know if you have seen this thread or not....

http://67-72chevytrucks.com/vboard/s...d.php?t=413551
.

[PbFut]

Thanks Doc. After not being able to get the dark blue wire pin, the pump lead, I concluded that the switch was bad. I've not tested the pump by grounding the leads as yet. The motor works at both speeds and returns to home prior to me digging into this. Ordered a switch. I'll hold off further testing until the switch is delivered.

[dmjlambert]

The back of the switch is swaged to hold it together. You can probably test it when removed from the truck with an ohm meter. It has 3 lugs on it, each of which should ground to the switch case when pushed or turned to certain positions. In low speed 2 of the lugs should conduct to the case, in high speed 1 of the lugs should conduct to case, and in low or high speed pushing the button should conduct the 3rd lug to ground.
Take the switch apart and clean it up with WD-40 or DEOXIT D5. Take it apart carefully so springs and other parts don't get lost and so you can see how it goes back together. Then put it back together. That is how I dealt with mine.