Looks Like Body ECU time (rear wiper)
- Thread starter Craabs
- Start date
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Maybe check your grounds. Toyota switches through the ground loop.
maybe a wire is pinched or cracked in the door jam loom for the top hatch. Maybe the brake light somehow turns it off?
The 20A fuse for it. Not sure if its under the hood or under the panel near the driver's side left foot.
Good place to start since the wire loom for both the motor and the 3rd (upper) brake light run out the top of the rear body opening and through the rear hatch. IIRC, there's a factory ground behind the DS lower quarter trim in the cargo area, just above the 12V outlet. However, the EWD will tell you for sure where each system grounds. Surprisingly, for as many electrical systems are on the LC, there's not that many factory ground locations.
Consider getting an Electical Wiring Diagram, they're not that expensive (!$50 at books4cars.com) and invaluable for tracking down goofiness like this. Might as well get the FSM's while you're there too...
pretty sure it's rear only. Theres a diagram on the back of the fuse cover, just follow the map to the fuse!
The fuse runs both. The rear wiper motor shares a ground with the rear brake light, starting from within the lift gate. There is also (at least on a 2000 MY) a rear wiper realy in the lift gate. Seems like the problem could be anywhere from the instrument ECU (problem = ?), to the rear wiper relay (stuck closed), to the switch itself (shorting to run position). Though not quite sure why the brake would stop it - though they share the instrument ECU and a ground in common...
The common ground wouldn't be enough to cause the motor to run unless the relay was energized. Electrical gurus/geeks may have a better interpretation of the schematic than I do...- Thread starter
- #12
I was considering that as well. Puting a factory type switch in one of the blanks on the dash. But after I get done running wires ect, $200 for an ECU doesn't seem that bad (not sure what they cost but think that is what I read somewhere).
Right now I'm thinking seat position must make it function correctly, because my wife drove it today and said it works fine
Right now I'm thinking seat position must make it function correctly, because my wife drove it today and said it works fine
I did a "good enough" fix for $20 using a wireless 12v relay.
see my thread:
https://forum.ih8mud.com/100-series-cruisers/325896-20-rear-wiper-fix.html#post4890933
see my thread:
https://forum.ih8mud.com/100-series-cruisers/325896-20-rear-wiper-fix.html#post4890933
I did a "good enough" fix for $20 using a wireless 12v relay.
see my thread:
https://forum.ih8mud.com/100-series-cruisers/325896-20-rear-wiper-fix.html#post4890933
see my thread:
https://forum.ih8mud.com/100-series-cruisers/325896-20-rear-wiper-fix.html#post4890933
If it's only $200 then that seems the way to go but I doubt it's that cheap. Leave the wiper stalk there and use it as normal, intermittent function wont work but normal wipe and wash should.(Will have to have a better look at the diagram)
Can't you just open the ECU and figure out if there is a bad relay inside there and replace it. I remember doing this on my 4runner rear power window ecu and paid a mere $3.00 for a new relay to fix the ecu.
[bringing this thread BTT instead of making new post, since my problem is exactly the same]
Craabs - So you've been problem free for a year now? Anyone else know the fix for this specific problem? Rear wiper stuck on except for when service brake applied?
I'm having the same issue right now. Worse yet, my wife is the one driving our 1999 100 series 200 miles away from home with both kids in the car! She just called me stating she wasn't even using the rear wiper and it went on, but it temporarily turns off while the service brake is applied. Anyway I hope your problem hasn't come back, but if anyone has a fix for this I'd appreciate it. Here was my "over the phone" temp fix assuming pulling the fuse wouldn't work;
1. pull rear wiper away from window
2. pull wiper blade off
3. wrap end that is now exposed with baby sock* and fasten it with one of her 50 hair ties (located on 4wd shifter) onto the sock.
4. do NOT flex wiper arm back up against window, just allow it to function in the air until she gets home.
* sock is used as safety if the arm decides to snap back against window for any reason!
Any help appreciated...
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Well just for the record. My wife is home and I just disconnected power to the unit itself.
Just so this is documented; I was only able to find a fuse for "WIPERS" that didn't differentiate between front and rear. I chose for now to remove the back panel, around rear glass, and disconnect power to the actual wiper motor, (approx. 1' towards drivers side of actual exterior wiper blade).
I'm in central CA and don't get snow etc. I've only used the rear wiper on my 80 and 100 a couple times and none were absolutely necessary.
Anyway still trying to find the problem with "always on" but stops with brake pedal pressed. Weird?
Just so this is documented; I was only able to find a fuse for "WIPERS" that didn't differentiate between front and rear. I chose for now to remove the back panel, around rear glass, and disconnect power to the actual wiper motor, (approx. 1' towards drivers side of actual exterior wiper blade).
I'm in central CA and don't get snow etc. I've only used the rear wiper on my 80 and 100 a couple times and none were absolutely necessary.
Anyway still trying to find the problem with "always on" but stops with brake pedal pressed. Weird?
Has anyone found a fix for this? My rear wiper has been going crazy since I replaced my battery a couple of hours ago. It's pitch dark here so I am planning on looking some more this weekend but I have not seen anyone really write up a solution. Funny enough the wiper stops when I push on the brakes... Would this be a ground issue in the rear hatch? And if so where should I focus my attention
Thanks for the help everyone
Thanks for the help everyone
There's a plug in the bottom left corner of the rear hatch, which has a habit of soaking up water, and giving you gremlins. In addition, it has a foam wrap which keeps the water in for days/weeks. I suppose the humidity comes in through the seal around the high stop light, which is known to fail after a few years (10+ ? ).