Hey All/

Spent the day doing battle with the Money Pit. Along with the failed emission test (other thread) the windshield washer didn't work. I need this for state inspection too. It worked at one time but since I almost never use it I'm not sure when it stopped.

95 Blazer, 4.3 Vortec type W, 4 door, 4wd, auto, 160,000 miles

Twist the **** and the wipers turn on but the pump doesn't. I checked the obvious. Power to the pump- pump works. Pump to ground - good. Checked the switch with a volt meter- switch seems OK. I changed it with a junk yard switch and have the same problem. So I don't think it is the switch.

I'm thinking broken wire. I found a grey wire out of the switch that get voltage when the washer switch is turned. I ran a jumper wire from there to the pump. Pump works! Wipers don't . Disconnect the jumper wire, wipers work, pump doesn't. Apparently there is more going on here than a simple on off condition.

So where do I look next? Wiper motor? What controls the intermitent function of the wipers?

Almost forgot. The rear wiper works but not the rear washer. Same problem. punp is good but doesn't get power when the button is pushed.

Thanks,
Having a cold one getting ready for tomorrows battle.

Mike

 

It sounds like there is a problem with the delay/speed/wash control inside the wiper motor. This controller senses the resistance on the pulse/low output from the wiper switch and determines what function is being requested. For pulse 1, battery voltage goes through 3 resistors inside the switch then out to the controller. In pulse 2, only two resistors are between the controller and battery voltage. For wash requests, only one resistor is used.

Here's the wiring diagram:

 

Thanks. That looks like what I need.

Mike

 

I have the same issue with the washer on a 1998 Blazer, I seem to get power to the green wire at the steering column, but none at the washer pump. The wipers were also playing up, so replaced the pulse board, this fixed the wiper issue but still no washer. Wipers do come on when washer switch turned. Any help would be gratefully received!

Thanks

Ian

 

Did you test voltage on the pink wire to the pump? If you supplied 12 volts there would the pump work?

 

On mine it has a green wire, I have voltage at the steering column but not at the pump end. The pump does work with 12 volts supplied.

 

I guess I was initially looking at the wrong pump, tracked it back to a damaged wire, now working fine Thanks for the help!