First off , they are fully covered in the FSM, see that here in section 8E:
The FSM does show a step by step diagnosis, and assumes you can diagnose this simple path, seen here in the schematics are chapter 8A-90 and 91 and 92
Wiper fails for 5 reasons, a voltmeter check finds the truth every time.
1:Bad fuse, 2:bad wires to motor, 3: bad motor, or 4: jammed linkage between motor and blades (look) , 5: the wiper combo switch is bad,
The wiper motor has 2 power sources. (3 counting high/low)
1: the main power pin ,Pin 1 or 2 , low or high must have 12v, or the combo switch is bad. (connections ,aways)
2: the keep alive pin. (sustain) pin 4 on motor. 12v. If not, (0V) the fuse is blown.
The Main power pin starts the motor moving, then the keep alive pin, sustains the sweep even if you turn the wiper OFF . this is done inside the wiper motor casing ( via a cam switch inside) so the wiper can stick, in mid stride, if the cam switch inside is bad.
Tests, are easy check for 12v to the 2 pins ( sustain and hi/lo as appropriat), if voltage 12v, is present in action, then the motor (and insides) is bad, or is jammed at ANY POINT.
Only carefull disassembly, and inspections, can find a jam.
The motor must be grounded, per the schematics, page 90-92 above, (click below photo to zoom it)
The washers: Front or Rear. (pump and tanks are in engine bay marked washers) (assumes its not freezing outside, and running antifreeze Type washer fluid, if it is freezing)
There are 2 pumps on some 4 door cars, see the same 8E link above for washers and the same 90/91/92 pages for schematics.
The pumps can fail only 2 ways, electrical or hydraulic (water) way. It's just a simple water pump.
If the pump receives 12vdc to the 2 pins, then the electric feed is GOOD. (a 1 minute volt meter check, yes, 2 persons, one to turn the switch.)
Using 2 persons:
Someone Keys on and activates the washer, buzzzzzz, no buzz ? check the washer fuse, see fuse link above, same fuse as wipers.
If no buzz, ?
Then check for 12vdc at motor pins, as person 2 activates the switch, got 12v?
Yes 12v, motor is bad,
Yes, 12v , pump is dirty packed up with dirt. clean pump, if it buzzes now its good. (usually , slight change of impeller bad, look at it carefull)
No, 12v. i get 0v. switch on combo is dead.
No buzz, got 12v. remove the hose to the pump/motor, buzzz now? no , then pump is dead,
Yes, buzz, got 12v.,hose off, the hose must be clogged up. clean it. end to end.
If motor buzzes, it should pump water (cleaner & water solution), with hose pulled. If it does pump now, hose off, the line is clogged. (or nozzels)
Disconnect the nozzles. water flows now ,out the tube end? yes, then the nozzles are clogged. Both can at once.
The rear line is very long and can clog at any point, Mine 2 lines (4door) had check valves in the lines near pump, about 1foot from pump. They were packed. I cleaned them and bingo, free fix. (very tiny brass fittings, pencil eraser small.
If the motor buzzes, remove the hose at the nozzle, does water flow now with pump on?, yes, then clogged nozzles.
If same check shows no flow, and motor pumps water, then the line is clogged.
Clean the tank of all debris. So it won't clog again.
END.
rev 1 ++++ 3-12-2011