Windshield washer not pumping

[email protected] · April 19, 2012

2007 Chevy Express Van 3500 6.0L

Washer does not pump. I can ID 2 fuses and one relay for the wiper in the owners manual but nothing specific for a fues for the the pump.

Assuming it is the pump I went ahead and learned how to get to the pump without pulling the complete grill. Now I seem to have a problem that I can't figure out.

Disconnected wires from pump and tested with Vom got 12v for a couple of seconds when the washer was actuated so this means no electrical problems.

Pulled the pump and did a bench test and it ran when I applied 12v.

Pluged the pump back into the harness but the pump does not run when the washer switch accuated.

Ideas?

Doug_Scott · April 19, 2012

2007 Chevy Express Van 3500 6.0L

Washer does not pump. I can ID 2 fuses and one relay for the wiper in the owners manual but nothing specific for a fues for the the pump.

Assuming it is the pump I went ahead and learned how to get to the pump without pulling the complete grill. Now I seem to have a problem that I can't figure out.

Disconnected wires from pump and tested with Vom got 12v for a couple of seconds when the washer was actuated so this means no electrical problems.

Pulled the pump and did a bench test and it ran when I applied 12v.

Pluged the pump back into the harness but the pump does not run when the washer switch accuated.

Ideas?

When you checked the connector for voltage, did you check the voltage across the connector, or did you probe one side of the connector with the ground probe connected to the chassis/battery/or some other known good ground? You need to verify there is a good ground before you go any further.

[email protected] · April 20, 2012

I checked the voltage across the two ends in the connector. I saw 9 volts one time and 11 another but it is difficult to get a good connection while holding the probes and the connector. Only have a second or two at most to get the reading.

I will check the ground wire to chassis tomorrow and get ohms so that will tell me if there is a problem with the ground side. Since the power is on for a short time is this controlled by a relay or some electronic circuit? Where is that controller?

Haven't bought the factory service manuals as they are $200 so am hoping I don't need them but if I get more hard to solve problems like this having a wiring diagram would be helpful.