I need to replace the sunroof glass of a 2003 mercury mountaineer

You need a good person with a pro grade scan tool computer. That should give a hint as it is likely to be sensor related. Change the fuel filter anyway.

Where is the fuel filter located on a 2003 Mercury Mountaineer?
It's under the vehicle in the fuel line from the tank to the engine.

where is the fuel filter located - 2003 Mercury Mountaineer

Video

https://www.google.com/search?q=2003+Mercury+Mountaineer%2C+replace+fuel+filter

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First off this is controlled by a module (computer) The switch would only have five volts . 5volt reference voltage from the control module . Not knowing how to test the electrical circuit's for this could be expensive . Short out the module or 5 volt ref. voltage circuit inside the module.
Your best bet , take it to a qualified repair shop . Look at a wiring diagram here http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model and engine size . Under system click on body & accessories ,then under subsystem click sun roof . Then click search button then the blue link . Now tell me you under stand what's happening here .

Power Sunroof System Components
The power sunroof system consists of the following components:
• Sunroof control module
• Sunroof Opening Position Switch (SOPS)
• Sunroof switch
• Sunroof motor/actuator
• Sunroof glass (spoiler type, with glass sliding above roof)
• Sunshade
• Rail and track assembly upon which the sunroof glass rides
• Power supply for the sunroof control module: SUNROOF 20 A fuse
• Ground from G302

Sunroof Opening Position Switch (SOPS)
The SOPS tracks the position of the glass through 2 limit switches:
• Soft stop limit
• Vent limit
The sunroof control module monitors the limit switches and based on the inputs determines the position of the sunroof glass. As a limit switch closes, the 5 volt reference will be shorted to the sunroof limit switch low reference circuit, pulling down the 5 volt reference to 0 volts.
The sunroof control module understands the position of the sunroof glass based on the different input combinations through the sunroof limit switch soft stop signal and sunroof limit switch open vent signal circuits.

Power Sunroof Does Not Close
Perform the Initialization/Teach Process any time a new sunroof motor actuator is installed in the vehicle or any time an existing sunroof motor actuator is removed from the vehicle. Refer to Sunroof Motor/Actuator Initialization/Teach Process .

Hello, I can give you some advice about this so please don't slam me for not having a diagram. If you put an Insurance claim, then you can go to your Insurance carrier about this problem. Although the shop was paid to fix your vehicle, the shop will want more Insurance work in the future. Having a bad repair history does not get a shop repeat business.

If you paid with a Credit card, there are some Premium cards which will intercede for shoddy or defective merchandise. Its another angle to get your vehicle properly repaired.

You are right about the Legal stuff. One problem you will have is your State law about Dollar limits on suits. Small Claims has a limit, higher amounts will need to go to a higher level Court. You must file in the proper Court for the amount of money you wish to collect.

Now about your Sunroof. I suspect that your problem could be a blocked drain. It is quite possible to make matters worse by chalking or sealing the sunroof so much that a drain is blocked. You could also have fragments of glass jammed in the drain lines. Sometimes you can use air pressure to clear the line, but if something is really embedded, the lines would need to be pulled out and replaced.

Some of the vehicles require removal of the Headliner to even work on the Sunroof and that requires talent and the right tools. You also need to Identify the Manufacturer of the Sunroof. Ford Motor, like other Car companies, had more Suppliers 10 Years ago and more than 1 Supplier could have made Models to fit your Mountaineer's Sunroof.

I tell alot of my clients to go to a Salvage yard and see junk vehicles for an idea about how this stuff is built. You may be able to find some drain lines and see where they go and rip them out for your shop to install. Don't under rate the help that Parts Counter people at Ford or Mercury Dealerships can give you. I have found they are all eager to supply photos straight out of their look-up computers.

I hope my solution is very helpful to you and Good luck on this problem.

did it stop working while it was in the shop or a day or two later?

if it broke in the shop it would fall into the duty of care to your vehicle. kick up a fuss if you havnt already paid for it. but if you have, goodluck getting any money back from a dealer.,

THE ELECTRIC DRIVE SYSTEM FOR POWER SUNROOF IS NOT ADJUSTABLE.DONT REMOVE THE SUNROOF MOTOR UNLESS THE SUNROOF IS COMPLETELY CLOSED.OTHERWISE A NEW MOTOR WILL HAVE TO BE INSTALLED AND TIMED WITH A TOOL THAT COMES WITH THE NEW MOTOR.THE GLASS PANEL CAN BE ADJUSTED.OPEN THE INTERIOR SUNSHADE ALL THE WAY BACK AND OPERATE THE SUNROOF UNTIL FULLY CLOSED.THERE ARE THREE GLASS MOUNTING SCREWS ON EACH SIDE OF THE SUNROOF OPENING.INSIDE THE VECHICLE LOOSEN THE SCREWS SET THE FRONT EDGE OF THE GLASS TO BE JUST 1MM BELOW THE SURFACE OF THE ROOF.ADJUST THE GLASS AT THE REAR EDGE TO BE JUST ABOVE 1MM THE ROOF AT THE REAR TIGHTEN THE SCREWS.

SECTION 501-09: Rear View Mirrors 2002 Explorer/Mountaineer Workshop Manual REMOVAL AND INSTALLATION Exterior Mirror Glass Removal
NOTE: Exterior mirror glass is serviceable only on vehicles built after July of 2001.

NOTE: Passenger side exterior mirror shown, driver side exterior mirror similar.
All mirrors

1. Position the glass in the full up position.

1. Locate the notch at the bottom of the exterior mirror glass.

1. Release the exterior mirror glass.
   1. Insert a long flat-bladed screwdriver in the notch.
   1. Push the screwdriver into the notch until the glass is released.

Heated mirrors

1. Position aside the exterior mirror glass.

1. Disconnect the electrical connectors.

All mirrors

1. Remove the exterior mirror glass (17K707) passenger side or (17T675) driver side.

Installation
Heated mirrors

1. Connect the electrical connectors.

All mirrors

1. Position the exterior mirror glass on the exterior mirror motor.

1. Place a hand against the back of the exterior mirror housing and a hand flat against the exterior mirror glass. Press the glass in place until fully seated.

It sounds like the inner latch that is bolted onto the gate itself is either off centered or the spring is gone. You can replace it easily. You can pick one up in a junk yard for a couple of bucks. To replace just open the hatch and remove all screws from the panel. Then pull the panel toward you to pull the clips from the body. once the panel is loose, push the panel in an upward motion toward the roof of the vehicle. This will expose the latch itself at the top of the opening between the glass and the gate. remove the latch wiht a 10 millimeter socket and replacew it with the one you just purchased. Try closing the glass very slowly before tightening fully. Replace the panel.

There are 4 holes on sun roof to drain water from up. You have to check & Clean those lines....

there should be a hole of sorts around the front of sunroof that is to drain water from around sunroof if it is clogged then you car will leak.

possible solution

undo all screws. use 2 large flatscrewdrivers to see where the plastics poprivets are.take your time and your panel will come off. to put on align panel to rivet holes use hand like hammer