2000 Passport Rear Wiper not working

[jmertz27]

Hello all, I have read through this forum, searched for answers to my particular question. My 2000 passports rear wiper morot does not come on, however whn I remove it from the car it works with power applied to the red and black wires. I have read about the relays, however I do hear the relay clicking while pressing the rear wiper switch. Could the relay still be bad? I get 12 volts to the rear wiper harness with and without the switch actuated. I do have the rear door closed, and the window switch actuated. if i pop the window release button, the 12 volts drops to 0 as expected. With the relay sound coming from behind the glovebox when I do actuate the rear wiper switch, thats kinda telliung me the switch is working, I know the motor is working, so could it still be the relay cosidering its clicking when actuated? This all statred last week, wife informed me the rear wiper was stuck in the up position and would not rotate down, the next day she tried it again, it went down, worked in the am, then was dead once returning to her car, and has not worked since. Any suggestions/help? Thanks to all in advance! Jim

[OnTarget]

Try this:

Have someone stand behind the vehicle while you turn on the switch from inside. It's possible the nut is loose on the wiper arm and just needs tightening. When it's loose, it turns freely without gripping the arm.

That's what was wrong with mine.

[jmertz27]

We have tried that, the motor is not turning at all. It appears dead, however it does work when directly wired. Thanks for the suggestion though!!

[Gizmo42]

Its the relays. The clicking when you push the switch means the coil of the relay is good, but its the contacts that go bad. You get 12 volts when the switch is on or off because for some weird reason Isuzu likes to switch the ground leg instead of the power leg.

[jmertz27]

I replaced the relay today, I got one from a 1999 Rodeo and the board was working when pulled, I transferred the relay over, and the rear wiper still does not work, any suggestions? I replaced RY4 only, didnt know if I needed to do one of the others or not. The board from the 1999 had more connections on it, but the relays were the same.

[Gizmo42]

Could be one of the other relays causing the problem. I know when I was testing mine before replacing that 2 of the relays allowed the rear wiper to operate. I replaced all 3 of mine just to be sure.

[jmertz27]

Update... I got my rear wiper working by replacing the other relay RY3 as shown in the upper part of this link:

http://forum.planetisuzoo.com/viewtopic.php?t=5608

I first replaced RY4 and it did not fix the problem, It was indeed RY3, I hope this information can help others down the road.

After extensive troubleshooting, it appears like was said in one of the forum topics I read, that there are 2 relays controlling the rear wiper, one for controlling it altogether, and another for its constant delay function it has which is not variable by the owner. The rear wiper only runs constant if you depress the washer function, then for a few cycles it keeps running. Its quite complex, and it really did not need to be. I could only imagine the repair bill I would have incurred had I taken this problem to a repair garage.

Thanks to all whose help quided me along the way!!!

[Gizmo42]

I might have to replace at least one of mine again. Works fine in the wipe function but if I use the washer it sticks and will keep going until I hit an appropriately large bump. Ran for almost 15 minutes one time. I try to not use the washer function now.