Join Date: Jun 2006
Location: Eastern ON Canada
Car: 07 OBW 2.5i D-4AT
Feedback Score: 5 reviews
Edit: see post # 6 below
The front washer motor is turned on and off by switching the ground side. In other words, 12 V comes from a fuse (same fuse that powers the front wipers, so if they work the fuse is good) to one side (one wire) of the motor. The other wire goes to the washer switch on the steering column which connects it to ground to turn the motor on.
To troubleshoot, the first thing you need to check is whether or not, with the key at ON, and the wires to the front washer pump disconnected, one of the two wires (might be yellow with a blue stripe) has 12 V on it.
If there isn't 12 V on one of the wires, then the problem is between the washer wire and the fuse. If there is 12 V on one of the two wires, continue by connecting the two wires to the motor, and check that there's now 12 V on the other wire (might be light blue with red stripe) . In this case the 12 V should be coming from the first wire, through the motor to the second wire.
If there isn't 12 V on the second wire, then there's a problem in the motor. If there is 12 V then the motor has continuity.
If there is 12 V on the second motor terminal, turn the key OFF. Disconnect the wires from the motor. Now using your multimeter set for Ohms (lowest range), test for continuity between the second wire and ground. The reading will normally be very high. Then, have someone pull the front washer switch. The resistance should drop to a very low value. (This is the switch grounding the low side of the washer pump.) If it changes,but not to a fairly low value, then the switch or wiring through the switch could be bad.
Last edited by plain OM; 02-04-2013 at 06:59 PM.
Reason: add ref to posts 6