Windshield washer pump mystery?
#1
Windshield washer pump mystery?
My washer pump stopped working so I went down to Napa and got a new one, $20 and put in in and...nothing. The pump itself is not a bad part as I hooked it right to the battery and it works fine. It's definitely getting power, when you hook the volt meter by itself to the wires and press the washer fluid button, you get power. When you hook up the wires to the washer fluid pump and put the volt meter on there and press the wiper fluid button nothing happens...aargh. Of course I have to get inspection done and I'm getting frustrated, any thoughts or suggestions??
#2
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Use the multimeter BEFORE you start replacing parts. Even $20 ones.
You have a bad switch. http://personal.utulsa.edu/~nathan-b.../5wiperand.pdf When the contacts close, there's enough dirt or corrosion that it makes a high-resistance connection. Your multimeter draws only a microscopic amount of current, so it "sees" the voltage through the resistance. Your pump pulls more than an amp, so the voltage drop across that high resistance pulls the voltage down to zero.
I don't know of anyone who has repaired that switch, but a replacement won't be cheap so it's certainly worth a try. And while I hate "hacks," if you need the washer pump for inspection, you could consider wiring in a plain-ole push button switch as a bypass.
(I'm assuming your measuring technique is good, and you didn't just mis-connect something. Since removing the switch isn't too easy, if it were me I'd repeat your steps to be sure you get the same result the second time.)
You have a bad switch. http://personal.utulsa.edu/~nathan-b.../5wiperand.pdf When the contacts close, there's enough dirt or corrosion that it makes a high-resistance connection. Your multimeter draws only a microscopic amount of current, so it "sees" the voltage through the resistance. Your pump pulls more than an amp, so the voltage drop across that high resistance pulls the voltage down to zero.
I don't know of anyone who has repaired that switch, but a replacement won't be cheap so it's certainly worth a try. And while I hate "hacks," if you need the washer pump for inspection, you could consider wiring in a plain-ole push button switch as a bypass.
(I'm assuming your measuring technique is good, and you didn't just mis-connect something. Since removing the switch isn't too easy, if it were me I'd repeat your steps to be sure you get the same result the second time.)
#3
Thanks scope, that makes sense. In fact after I posted I went back out and tested the old pump and of course it works just fine, lesson learned. At least it was only 20 bucks...
Bypass switch it is!
Bypass switch it is!
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