As many RAV4 owners did, I noticed that the rear wiper swing direction makes little sense. In my experience, it should be reversed. Otherwise, during a snow storm, wet snow has tendency to pile up between the rear windshield and the spare tire cover to a point that the rear wiper arm can no longer move. In addition, the arm blocks some rear window area where it is normally parked.
I was thinking for some time about changing the rear wiper arm direction without significant modifications, and searched the Internet for some clues. I have found this post: http://www.3si.org/wiki/index.php/Stealthy_Wiper_Mod where it describes modifications for a Dodge car to do just this. Although I was a bit discouraged that the person had to do some welding during the modification - I was not ready to do that much work.
Anyway, I hoped that RAV4 rear wiper motor assembly is designed the same way, so I can follow the post ideas. I opened up my car rear wiper motor assembly, and found that the modification can be done in a MUCH easier way (my respect to Denso engineers!). Below is the write up of the modification, after which your car rear wiper arm will park behind the spare tire cover, and still clean the rear window properly (it has about 170 degrees swing).
Look at the image gallery links below to see how the rear motor assembly looks like and how you rotate the brass contact plate on the flywheel.
Please follow those steps at your own risk - I am not responsible for any potential damage to your car interior/exterior, electric and/or mechanical systems.
1. Remove tailgate door inner covers by pulling then out with your fingers (there are screws to remove - just a set of retention clips), starting from the piece on the top of the rear window, then sides, then the bottom. Be careful not to break the retention clips;
2. Swing open the rear wiper arm cover at the area where it connects to the rear wiper motor shaft. Use a 10 mm wrench to remove the retaining nut; Remove the arm from the shaft;
3. Remove three 10 mm bolts holding the rear wiper motor assembly. The bolts will stay attached to the assembly. Disconnect the wire harness from the assembly. Remove the assembly from the tailgate;
4. Open up the assembly by removing 4 screws from the assembly top cover. Be prepared that it has lots of grease inside (see the image link below), so use a paper towel during the process;
5. Once you open the cover, you will see how the motor is connected to the rear wiper arm shaft through a flywheel and a set of arms. Note all the connection, so it will be easy for you to assemble them back;
6. To my delight, all the internals of the assembly had no retaining clips - it is possible to remove them without any effort. Remove two swing arms - one made of white plastic and one made of metal (note how they are connected to each other!), until you free up the white plastic flywheel;
7. Remove the flywheel from the assembly body (it simply falls off its shaft). Turn the flywheel around - you will see a brass contact plate. The plate has a special shape to control how the three sliding contacts at the bottom of the assembly body connect to each other during the wiper arm movement. The plate allows the assembly electronics to detect the starting and ending point of the wiper arm movement. To reverse the arm swing direction, you need to turn the plate 180 degrees;
8. Remove the brass plate carefully. Be sure not to bend it or scrape. I used an Exacto knife to gently lift up the plate around each of the 4 tabs it has. The tabs grab the flywheel in the 4 pre-formed holes;
9. Simply rotate (not flip!) the brass plate 180 degrees, so the plate cutout goes the opposite direction. You do not need to make any modification to the flywheel, as the plate tabs go into the exiting 4 holes in the flywheel body. Although the flywheel has some indents to accommodate the plate cutouts, I decided not to worry about it - the sliding contacts will accommodate slight decrease in the distance between the plate and the contacts. Make sure that the plate sits close to the surface of the flywheel, otherwise the sliding contacts will be damaged by the plate edges; It is a good idea to use a very fine sandpaper to round the plate edges a bit in the places where the sliding contacts meet the plate (you will see the grooves made by the contacts). Bend the tabs inside the holes so the plate sits tight;
10. Add some fresh grease to the flywheel shaft and the plate, and put the flywheel back. It does not matter in which position - electronics will find the starting point later;
11. Add more grease to the assembly, and put back two arms the way they were sitting inside. Put the assembly cover back (wipe out any debris around the cover seal), and add 4 screws to their original places.
12. Plug the wire harness back to the assembly. Place the assembly back to tailgate with 3 nuts. Please note that if you are tempted to check whether the motor assembly works, then the assembly body needs to have contact to the car body - otherwise it will not work (I had a heart stopping moment when the motor showed no signs of life after I plugged it to the harness, bit let it stay loose :shock: );
13. Turn on the rear wiper, and check that it indeed swings in the opposite direction now. Attach the rear wiper arm to the shaft in a way that the arm starting location is behind the spare tire cover. Once it it is attached, check that it swings in and out, and parks in a desired position behind the cover.
So the mod works great so far - the arm still has about 170 degrees swing, and I have more rear window area free to monitor incoming traffic. I will check this winter if the mod improves the wet snow handling. One potential drawback I can see is that the rear wiper arm will be buried by snow accumulating behind the spare tire cover, so I will need to free the arm up before turning the car on. But I would have to remove snow from that place in any case.
Good luck and hope this write up helps you guys.
Image gallery:
1. Rear wiper motor assembly. Note a black plastic box on top - ground wire for the motor:
2. Rear wiper motor assembly - opened up:
3. Details of the arm and flywheel links:
4. Arm and flywheel removed from the housing. Note the 3 sliding contacts in the housing body (covered by grease):
5. Flywheel and the brass plate:
6. Brass plate rotated on the flywheel:
I was thinking for some time about changing the rear wiper arm direction without significant modifications, and searched the Internet for some clues. I have found this post: http://www.3si.org/wiki/index.php/Stealthy_Wiper_Mod where it describes modifications for a Dodge car to do just this. Although I was a bit discouraged that the person had to do some welding during the modification - I was not ready to do that much work.
Anyway, I hoped that RAV4 rear wiper motor assembly is designed the same way, so I can follow the post ideas. I opened up my car rear wiper motor assembly, and found that the modification can be done in a MUCH easier way (my respect to Denso engineers!). Below is the write up of the modification, after which your car rear wiper arm will park behind the spare tire cover, and still clean the rear window properly (it has about 170 degrees swing).
Look at the image gallery links below to see how the rear motor assembly looks like and how you rotate the brass contact plate on the flywheel.
Please follow those steps at your own risk - I am not responsible for any potential damage to your car interior/exterior, electric and/or mechanical systems.
1. Remove tailgate door inner covers by pulling then out with your fingers (there are screws to remove - just a set of retention clips), starting from the piece on the top of the rear window, then sides, then the bottom. Be careful not to break the retention clips;
2. Swing open the rear wiper arm cover at the area where it connects to the rear wiper motor shaft. Use a 10 mm wrench to remove the retaining nut; Remove the arm from the shaft;
3. Remove three 10 mm bolts holding the rear wiper motor assembly. The bolts will stay attached to the assembly. Disconnect the wire harness from the assembly. Remove the assembly from the tailgate;
4. Open up the assembly by removing 4 screws from the assembly top cover. Be prepared that it has lots of grease inside (see the image link below), so use a paper towel during the process;
5. Once you open the cover, you will see how the motor is connected to the rear wiper arm shaft through a flywheel and a set of arms. Note all the connection, so it will be easy for you to assemble them back;
6. To my delight, all the internals of the assembly had no retaining clips - it is possible to remove them without any effort. Remove two swing arms - one made of white plastic and one made of metal (note how they are connected to each other!), until you free up the white plastic flywheel;
7. Remove the flywheel from the assembly body (it simply falls off its shaft). Turn the flywheel around - you will see a brass contact plate. The plate has a special shape to control how the three sliding contacts at the bottom of the assembly body connect to each other during the wiper arm movement. The plate allows the assembly electronics to detect the starting and ending point of the wiper arm movement. To reverse the arm swing direction, you need to turn the plate 180 degrees;
8. Remove the brass plate carefully. Be sure not to bend it or scrape. I used an Exacto knife to gently lift up the plate around each of the 4 tabs it has. The tabs grab the flywheel in the 4 pre-formed holes;
9. Simply rotate (not flip!) the brass plate 180 degrees, so the plate cutout goes the opposite direction. You do not need to make any modification to the flywheel, as the plate tabs go into the exiting 4 holes in the flywheel body. Although the flywheel has some indents to accommodate the plate cutouts, I decided not to worry about it - the sliding contacts will accommodate slight decrease in the distance between the plate and the contacts. Make sure that the plate sits close to the surface of the flywheel, otherwise the sliding contacts will be damaged by the plate edges; It is a good idea to use a very fine sandpaper to round the plate edges a bit in the places where the sliding contacts meet the plate (you will see the grooves made by the contacts). Bend the tabs inside the holes so the plate sits tight;
10. Add some fresh grease to the flywheel shaft and the plate, and put the flywheel back. It does not matter in which position - electronics will find the starting point later;
11. Add more grease to the assembly, and put back two arms the way they were sitting inside. Put the assembly cover back (wipe out any debris around the cover seal), and add 4 screws to their original places.
12. Plug the wire harness back to the assembly. Place the assembly back to tailgate with 3 nuts. Please note that if you are tempted to check whether the motor assembly works, then the assembly body needs to have contact to the car body - otherwise it will not work (I had a heart stopping moment when the motor showed no signs of life after I plugged it to the harness, bit let it stay loose :shock: );
13. Turn on the rear wiper, and check that it indeed swings in the opposite direction now. Attach the rear wiper arm to the shaft in a way that the arm starting location is behind the spare tire cover. Once it it is attached, check that it swings in and out, and parks in a desired position behind the cover.
So the mod works great so far - the arm still has about 170 degrees swing, and I have more rear window area free to monitor incoming traffic. I will check this winter if the mod improves the wet snow handling. One potential drawback I can see is that the rear wiper arm will be buried by snow accumulating behind the spare tire cover, so I will need to free the arm up before turning the car on. But I would have to remove snow from that place in any case.
Good luck and hope this write up helps you guys.
Image gallery:
1. Rear wiper motor assembly. Note a black plastic box on top - ground wire for the motor:
2. Rear wiper motor assembly - opened up:
3. Details of the arm and flywheel links:
4. Arm and flywheel removed from the housing. Note the 3 sliding contacts in the housing body (covered by grease):
5. Flywheel and the brass plate:
6. Brass plate rotated on the flywheel: