One-Touch Sunroof Open (DEI Timer Relay) Installation Instructions
by Toby Erkson

It is recommended that you have a Bentley shop manual as a reference during this procedure.

Remember, the compass directions of the car are always in relation to the centerline of the car with someone sitting in it. Thus, FRONT is where the headlights are, REAR is where the exhaust tips are, LEFT is the driver side of a USA car, and RIGHT would be the passenger side of a USA car. For those who know boats, LEFT is still PORT and RIGHT is still STARBOARD. This is important to understand as a standard because you may end up facing the rear of the car, thus your left & right will not be the same as the car's left & right :-)

These instructions are based upon the installation of the 528T pulse timer relay (here or here) in my 1995 Jetta III GL OBD I car for allowing a one-touch operation for opening the stock sunroof. This document is meant for someone who is comfortable and skilled to work on their own car and around wires, voltmeters and crimp-on style wire connectors. As always, it is best to read this entire document, test fit and 'eye-ball' everything so there will not be any surprises during the installation.


Installing the timer.
What the parts look like (generic automotive relay not shown):


Remove the motor trim cover by pushing back the sunroof perimeter trim from the headliner and freeing the rear lip of the cover. Pull down enough to clear the sunroof perimeter trim then pull cover back (to the rear of the car). Next, remove the lights/sunroof controls from the headliner by using either your fingers or a flat-bladed screwdriver to pry the assembly away.


Pull about 4 inches of the headliner away from the sunroof perimeter trim on the left side. Thread the DEI (DEI timer relay) from the motor opening to the switch opening. Slip the DEI above the headliner in gap to the left of the motor with the timer adjusting dial pointed towards the sunroof motor (see below image).


Put headliner back into place. Wrap the end of the orange DEI wire with electrical tape and tuck it away. I stuffed mine in the foam that's in front of the switch assembly opening.

This next step is where some wire crimping experience and comfort with wiring is necessary. Do not perform this next step if unsure or uncomfortable with cutting wires, crimping connectors or reading wiring diagrams -- have a friend or mechanic do it for you. Wire everything together as shown in the below wiring diagram:




Where the green wire is cut is where you would use male/female spade or bullet connectors to connect the ends to the generic relay (post #85) and the DEI (brown wire).

Close-up of the power supply tap in the flat, 6-wire connector located on the sunroof motor:


This is what it will basically look like when done. Note that I did wrap electrical tape around the posts on the generic relay to hold the wires securely to the unit and protect them from shorting against anything.


Stuff the wiring and generic relay into the switch opening, up and over to the driver side sun visor area. Push sunroof switch assembly back into place.

Adjusting the timer.
There is a power cut-off switch in the 3 positions of the sunroof:
  1. full close
  2. full vent open
  3. full open
These stop power to the motor once the sunroof has reached the end of its travel and thus keep the motor from "burning up", so applying power a little longer will not damage the motor. It is no different than manually pressing the desired button longer than necessary. So, with that in mind...
  1. Turn ignition switch to the Accessory position
  2. Turn DEI adjustment dial to the 9 o'clock position
  3. Push the sunroof open button and listen to the DEI relay. The relay should click off about 1 second after the sunroof stops
  4. Adjust the DEI dial very slightly. Clockwise to lengthen the open time and counterclockwise to lessen the open time
  5. Close the sunroof all the way
  6. Repeat steps 3 thru 5 until you are satisfied with the opening time
Note: I made my adjustments from the full open vent position (sunroof tilted up).
When satisfied with opening time, replace the sunroof motor trim cover. Instructions that came with the timer. Done!

-- End Of Document --