Mechanics

CHEVY WINSHIELD WASHERS DON'T WORK

2003 Chevrolet Silverado

Electrical problem
2003 Chevy Silverado V8 Four Wheel Drive Automatic

Winshield washer do not operate. I've checked the fuses which are in the box under the hood. I've changed the relay with no luck.

Are there other fuses to check?

Any help appreciated.

Tim
Avatar
SR-71
August 17, 2010.




Can you hear washer pump humming when opearting switch?

Bluelightnin6
Aug 17, 2010.
No. The relay doesn't click and the motor does not run.

Tiny
SR-71
Aug 17, 2010.
Okay, since fuses and relays are good than the washer motor is most likely at faulty. Supply 12v direct battery power to the washer motor, if it doesn't run than it's bad.

Bluelightnin6
Aug 17, 2010.
I would think if the switch in the turn signal lever has power, that the relay should click regardless if the motor is bad or not. The washer motor relay does not click at all even though it is good.

The washer fluid container is buried between the battery and the head lights and will require extensive dis-assembly to get to the motor and wiring, so an electrical diagram of the washer motor circuit would be nice before hand.

Thanks again.

Tiny
SR-71
Aug 18, 2010.
If the switch did not have power than not only would the washer be inoperative but the wipers and signals as well....Wiring diagram is below..


http://www.2carpros.com/forum/automotive_pictures/261618_Noname_2595.jpg



http://www.2carpros.com/forum/automotive_pictures/261618_Noname2_843.jpg


Bluelightnin6
Aug 18, 2010.
Thanks for the diagram.

Agreed. When I push the wash tab on the turn signal arm forward to start the cycle, the wipers cycle several times and then shut off as they should, however the washer fluid pump does not run. Again, today I checked the washer motor pump relay and found that the fuse is good and that the relay does not energize as it should even when a known good relay is substituted. Since the relay doesn't energize, the motor can't run and the wipers can.

I assume that this is a computer controlled function and no wire actually goes to the relay from the switch. That being said, I ran the battery dead a couple of months ago and am wondering if this could have something to do with it. Could this function be messed up in the computer?

Tiny
SR-71
Aug 18, 2010.
This could be a wiring issue still yet. The orange wire that runs from the wiper motor module (under the windshield cowl) goes to the fuse than to the relay. If this wire is disconnected/damaged than there will be no power getting from the wiper module (computer) to the fuse. If the fuse doesn't have a connection to the wire than there is obviously no way to send the signal on to the relay, therefore the relay doesn't energize. Check this orange wire out, again it is under the cowl. If it's good than the wiper motor module MAY be faulty, but with everything else working as it should, I find it hard to believe that the switch or the module would really be at fault here.

Bluelightnin6
Aug 18, 2010.
I'll check the yellow wire. In looking at the diagram it appears (it's small and hard to read) that the yellow wire from the module to the relay is a ground. The other side of the coil is hot and protected by the fuse. Is this correct?

Tiny
SR-71
Aug 18, 2010.
Yes, I know the forum doesn't like these large wire schematics but I blew it up best I could to fit here.

There is no yellow wire to the relay. The orange wire is to the relay and is the one that needs inspected. The yellow wire goes to the wiper fuse while the orange wire goes to the washer fuse than to the washer relay.
AD

Bluelightnin6
Aug 18, 2010.
OK, then I should be able to jump the +12v directly into the output of the relay (via the relay socket) and energize the pump to verify if it works or not.

Will report back what I find.

Thanks again.

Tiny
SR-71
Aug 18, 2010.

AD