Windshield Wipers

Variable Intermittent Wiper
The following explains how to install a 'programmable' intermittent relay which will give a intermittent time interval from 2 to 45 seconds. The time interval is programmed using the wiper stalk switch.

The relay is Bosch P/N 0 986 335 058. It should cost between $30 and $40 from any one of the following:

Automotive Performance Systems (800-423-3623)
Wolf Sport (800-342-8669)
VW or Audi dealers -- VAG P/N 1HM 955 531 A
The "A" is the important part, but this part has been superceded, so when you ask for it, they may try to give you a part that ends with "B", "C", etc. The "B" part does work, the "C" does NOT!

Installation:
This relay takes the place of the relay in position #9 in the main fuse box under the hood. The relay to remove is white and has a large 271 printed on the top. Its part number on the side was 443 955 531. Remove this and replace it with the 'programmable' relay.

Operation:

Turn the wiper switch to the intermittent position then turn it to off. The wiper will wipe once.
When you need the wiper to wipe again, you place the wiper switch to intermittent and leave it there. It will remember the time interval and repeat the wipe at this interval.
To change the interval, just turn to off (wiper will wipe) and then turn back to intermittent position to set the new time interval.
The relay is reset to a 6 second default interval when ignition is turned off.

Rear Wiper Problem
(Scott Malcolm)
Symptoms: Rear wiper skips and chatters and may become stuck out of resting position.
The problem could be the wiper itself or the motor. To find out which, run the wiper with the blade lifted off of the window. If the arm still has problems with movement, check out the motor, otherwise it's the blade.

Blade:
If it is old and not often used, the blade becomes "used to" a certain orientation and will no longer contact the window at a right angle, favoring one wiping direction while skipping in the other direction. Easiest fix is to replace the blade. The Bentley manual suggests bending the wiper arm by rotating it until the blade is oriented correctly.

Motor:
The lubricant/grease inside the motor will congeal and harden with age. If the wiper works fine at the end of a hot day, that's a clue that you need to relube the motor. The wiper assembly consists of a motor, attached to a spiral worm gear that's attached to a round toothed gear. The round gear drives an arm that moves the wiper shaft. On the back side of the round gear are 3 contact traces that rub against some electrical "wipers" that come through the wiper case to the wire connectors. What the wiper and traces do is reverse the motor direction when the end of the track is reached.The lube/grease which aids the gear trace/wiper hardens and lifts the electrical wiper off of the trace. If you open the case of the wiper (4? screws once you remove the inside hatch cover panel), and operate the windshield wiper, you may see some arcing and sparking through the gear. It is sort of an opaque white. I am not sure if the traces are riding up and arcing when the circuit is opening or if the electrical wipers are shorting out to the case. If you remove the hardened grease and replace with fresh stuff, the wiper will work.

The key to disassembly is to:

Remove Wiper arm
Remove little plastic cap
Find C-clip on wiper shaft. This holds rotating wiper shaft in place
Open up wiper "box" (where gears are) by removing the inside trim panel on the hatch, then the 4 screws
Push shaft thru and remove
Shaft removal allows arm removal which allows toothed gear removal
Remove crappy grease
Relube with white lithium grease
Reassemble in reverse
Enjoy smooth wiper action

Beware! If the motor becomes jammed during operation, it may continue to draw current. I have heard that the rear wiper circuit is grossly under-fused, so the motor will quickly heat up to dangerous temperatures before any fuses blow.