Body: Sunroof                                                                                                  FAQ Home

 Volvo Maintenance FAQ for 7xx/9xx/90 Cars                                                                                                                     Version 5.0

Sunroof Sticks When Closing.  [Symptom: I have a 90 740 GLE and noticed that the sunroof is getting stuck when trying to close. I took out the motor, lubed everything and the motor appears to work fine. Also when the sunroof is closed if you look on the outside it doesn't appear to be sitting flush like it should.] [Diagnosis:] If your guides are not broken then you may just be out of adjustment. Adjustment is accomplished by loosening a number of screws, moving the roof and re-tightening. A Haynes or Bentley manual will help you through. If you do need to remove the sunroof there is an easy method. Open the roof to the vent position. Use a screw driver or needle nose pliers to release the springs that hold the sunroof liner to the roof. Push the liner back into the space where the roof would normally retract. This will expose all parts, and adjustment screws. [Response: Rob Abel]  Our sunroof in our '93 940 acts goofy at times. Clicks and doesn't move - gets stuck - usually open - have had to close it manually by taking off cover and using screwdriver. On ours it's the switch. I take it out about once every two months, take it apart, clean up the contacts, and it works fine for the next two months.  The only manual that will adequately address this is the Volvo factory body manual (Body Fittings: Exterior/ TP 8202201). None of the others do.

Electric Sunroof Stuck Open: Alignment.  [Query] The power sunroof on my '91 940T has stopped functioning, and is stuck all the way "open" (tilted up, rather) and won't go back down. This follows a few weeks of CLICCLICKLCLIK when opened/closed, and some erratic operation. [Response: Kerry] (Applies to 1986 765) With your sunroof in the vent position you can remove the sunroof liner and check all the bolts on the mechanism and rail. To remove the liner:

1. Get a coat hanger and cut out the straight part. Bend the end to form a small hook
2. Pull the edge of the sunroof liner down at the end sticking up (remember your sunroof should be in the vent position)
3. You will see two spring loaded hooks which are attached to the sunroof liner and hooked to the sunroof. These hold the liner in place. They are at the back of the sunroof, one left and one on right.
4. You can unhook them with your coat hanger wire.
5. The sunroof liner can then be slid back out of the way (don't push it to far back)under the roof and above the headliner.

Sunroof Won't Open to Vent Position. [Tips from Ken Dibnah] If you have a 740 with an electric sunroof, when the roof is in the fully closed position you should be able to push the closed switch again and have the rear of the roof pop up to the 'vent' position. If you have a manual roof, after it reaches the closed position you feel a bit of resistance; you then continue moving the crank in the closed direction and the rear of the roof should pop up to the 'vent' position.

If your roof does not move at all, you must NOT pry up the rear edge manually as there are cast tracks at the rear of the panel that hold it in place and you will break, bend, or damage the tracks, roof or the panel.

Most likely it is out of alignment and too tight for the minimal leverage applied by the motor to move it, as well as being thoroughly gunked up. The secret to lack of motion is most likely binding in the up and down motion of the panel. If manual, try moving the crank back and forth, bearing in mind that the first motion the roof makes is that up and down motion at the rear of the panel.  If there is resistance to the crank motion immediately, there is 'likely' to not be any damage in the screw mechanism, just binding of the panel in the roof.

If nothing moves as you move the crank towards 'vent', push up gently through that small rectangular opening inside the headliner on the rear of the panel to help it along, by just pushing it free of the roof. The tracks at the rear of the panel move the panel up and down, either to pull it down before retracting or to pop the rear of the panel up for the 'vent' position, and if they are damaged or too gunked up, they will resist opening.  The device that is connected to the motor/crank via screw cables slides back and forth in these tracks, raising and lowering the panel, which will not be possible unless you can move the crank/motor. Try to get it high enough to be able to peer inside the roof from the outside to unhook the headliner clips - once you get those, all is revealed and you will be able to see why your roof is not functioning properly.

WRONG! Not on this run of 960's anyway.   It took me a while to figure this out, so I hope someone will benefit.   Basically the rear of the roof , when parked, was always about 5mm's below the roof line, while the leading edge was flush.  I can hear this at highway Speeds.

Don't do anything to the "push back guard", (not necessary) or look for springs or clips, (there aren't any.)  Just leave the roof in parked position.  Push back the panel was far as it will go without undoing anything.  Up on both side of the roof, parallel to the tracks, you will find one per side of black/grey injection molded, plastic strips. Lift the lower edges and they snap right out.

Now there are 4 bolts with an 8mm head. one each at the front and rear of each track, left and right.  Loosen each of these 1/2 of a turn.  Push up one corner at a time, til it's flush with the roof line, then cinch the corresponding bolt tight.  Snap the strips back in place and you are done.

• Close the sunroof.
• Pull down on the headliner just forward of the interior lights.
• Pull the sunroof lining back so it is inside the roof.
• Look at the control mechanisms to determine the extent of the repair.   Are they ok, are screws missing or are they loose? If the screws are loose, tighten them, if missing, find and replace.
• If the sunroof needs more extensive repair, remove all screws and lift out the sunroof.
• Remove the electric motor or manual crank. Doing this will allow for proper control mechanism centering, a procedure I needed to repeat.
• Replace the mechanisms by removing the two SMALL circlips with a small screwdriver. Do one side at a time so the other can be used for reference.
• Transfer the spring to the new control mechanism and place the new one where the old one was, make sure the small plastic covered tab is in it's slot and on top of the flat metal 'spring'.
• Replace the circlips, again needle nose pliers work here.
• Do the same to the other side.
• Align the control mechanisms with the slots for the small plastic covered tabs, slight back and forth motion works here.
• The control mechanisms should now lay flat and be loose, not tight under tension. The sunroof is supposed to be closed after all.
• You will notice the cranking mechanism is nothing more than a modified worm gear arrangement.
• Make sure the sunroof retracting mounts, up front and to the side, are properly positioned and as far forward as possible.
• Replace the sunroof.
• Replace the screws leaving them loose so the sunroof can be adjusted for height, which will be done now.  Do not try to operate the sunroof at this time since it is loose and the liner would be pushed back into the bowels of the car never to see the light of day!
• Adjust the sunroof height by operating the sunroof SLIGHTLY in the rearward position and also in the ventilation position, flipped up in the back.
• Close the sunroof and make adjustments. It should sit down slightly from the roof but there should be no gaps.  Make sure the spring clips are installed in the rear edge of the sunroof and the large springs are attached to the large pin on the control mechanism.
• Apply oil or grease to the control mechanism slots which should be an annual event. I found one of mine had dried out grease and was nearly ready to break.
• When you are happy with the positioning of the sunroof, move the liner forward and flip up the sunroof to reattach the clips to the lining.
• Operate the sunroof and enjoy.

Remove the motor as follows:

Remove the two screws holding the plastic cover (2 #10 torx screws)
Cut the headliner as required to get access to the motor - only cut areas that will be covered by the plastic cover. Obviously when the car was built, the motor was installed first and then covered by the headliner.
Remove two small Phillips screws near the rear of the motor housing, 1 10mm nut at the front, and one large Phillips screw that connects the motor ground to the body just in front of the motor (front and rear refer to the ends of the car that have headlights and brakelights respectively).
Withdraw the motor and undo the connector (may be a little easier said than done depending on the amount of slack in the cable)

Result: So far the sunroof has operated 100% reliably. I hope my conclusion about wear to the
cam follower was correct and that the roof will continue to work properly.

[Tips on Motor Electrical Overhaul from Pete Gotseff]

Testing:
1) If your motor "clicks" but doesn't move, remove motor cover (2 phillips) and get access to the motor connector (comes in from left side).  The blue and red wires at the two prong connector should be +12V or –12V depending on sunroof momentary switch position. If you’re getting proper voltage to the motor verify brown ground wire is well grounded (very important!).  If I recall correctly an improperly grounded motor will “click” but not move.
2) You will be removing the motor so it would be best to put sunroof in vent or closed position with a screwdriver on the manual override.   Either of these two positions will allow the motor and sunroof to be timed correctly when reinstalling the motor.
3) If voltage and ground check out – reconnect connector and unscrew (2 phillips) and unbolt nut (10mm) and let motor hang (not a good idea but what the heck).  Now test the motor while electrically connected including the ground.  Again, make sure the ground is well grounded.  BTW, if the motor moves you will have to retime the motor :-) more on this later. If the motor works normally it is likely your sunroof is binding and you should drop the headliner and dive headfirst into that problem.
4) If motor still just clicks test the motor itself by putting 12V across the actual motor terminals (not the connector) and see if the motor runs smoothly.  Reverse polarity to verify both directions.

 A properly working motor will rotate (as seen from the bottom and in vent position) CCW about 1 turn to closed, pause, push SR button again and CCW about 8 turns to full open. Not exactly sure about # of turns.

Repair:
If the motor still just clicks then it will likely one of the two microswitches located in the timing gear cover.

1) Pop off the three tabs and carefully rotate the white nylon cover out of the metal motor case leaving the motor wiring connected.  This plastic cover contains two microswitches, a selenoid (remember "click") and three small pointed plungers.  FYI: These plungers are actuated by the sunroof motor driven timing gear which remains in the case. The timing gear has three alignment points on three levels which correspond to vent, closed and full open.  The center point on the middle level is "closed."  This will help when you retime the motor.

2) Remove the micoswitch holder pin at the corner (some have a slot to adjust switch position and small retainer clip) and remove the microswitches as a pair (they are soldered together).  They can be removed without removing anything else by using a small jewelers screwdriver to move the microswitch plungers out of the way of the selenoid actuator.  Now, use photographic memory or paper to record colors of wires on each switch (you'll be sorry if you don't). Unsolder just one side of the common copper ribbon holding the microswitches together (just one side is good, leave the other side attached to the other switch). Then unsolder the remaining wiring (two black leads) which hold the switches to the selenoid.

3) With switches free test each one for high resistance through the normally closed circuit – the front (blue or red) connections to side terminals. My switch had 63 Ohms across these terminals when they should've been around 1-2 Ohms.

At this point you should find a bad microswitch.  You can repair (as below) or replace from a good electronics store (i.e. not Radio Shack)  be sure to get a switch with lug terminals not spade type.  Spade type will not fit when placing switches back into the cover.

4) Now open switch case by carefully drilling out one side of two small metal retaining rivets.  Punch rivets through with small screwdriver.  Open case carefully to avoid spring, switch assembly from flying behind/over/under workbench.  Sand contacts lightly with sandpaper. Reassemble case and epoxy switch case cover (you'll never do this again). Resolder switches and reassemble them into the cover.

5) Turn the motor manually with a screwdriver to ensure the three level plunger in the cover will fall somewhere between the three timing points on the timing gear.  But don’t align the gear points directly with the three level plunger – they will interfere when putting the cover back on. Replace the cover which contains the microswitches and selenoid onto the motor case.

6) I suppose now would be a good time to bench test the motor.  If no 12V supply is available (I use an old Sun computer power supply) test in the car (see below).
 

Retiming motor (electrically installed in car):
1) Make sure motor is electrically connected to sunroof connector and ground.  Now, run motor CW (as seen from below) until it stops, push on momentary switch again.  If no movement then motor is in vent position.
2) If sunroof is in vent position motor can be reinstalled.  If sunroof is in closed position push sunroof button to rotate the motor CCW to the closed position. Now the motor can be reinstalled.  This may take some trial and error but if the motor is working correctly you’ll figure it out eventually – HeHe.