Cadillac XLR HUD doesn't display.

Question edited for clarity.
Question moved to model category.

In the link

https://www.google.com/search?q=2005+cadillac+xlr+replace+door+switch

..

The instrument cluster HUD and the instrument cluster HUD dimmer switch are both connected to the instrument panel wiring harness.
The instrument cluster HUD dimmer switch performs the following functions:
• Provides power to the instrument cluster HUD
• Varies the intensity of the display image
• Controls the motor driven mirror
• Varies the height of the display image

The HUD dimmer switch gets power from IP / IGN fuse -10 amp Fuse Block
Right side of the IP, in the IP compartment opening

You just need to use a flat screwdriver to pry the door switch from the slot where it sits, disconnect the wiring from it and install the new one in reverse order

Hey Laurie,
There is several things that might cause the distortion, polarized sunglasses, a non-hun windshield, the HUD lens is dirty, plastic coating on your glasses, the HUD is distorted if you are tall. if you wear bifocals , the HUD might to fall into the progressive range and isn't quite in focus. possibly the HUD is in focus with your left eye but not your right eye???
Just a few things that you might "look at"... :)

Good lord there are fuses everywhere in that truck if I remember right, you'd have been better off asking about the problem I think.. try here
http://www.jeep4x4center.com/knowledge-base/index.htm#service
find your truck, pull up the PDF then on your keyboard hit the find box (F3?) punch in "fuse" and run down the list...

For the basic panel
Cavity/Fuse Diagram (1996 Grand Cherokee, passenger side kick plate to find, Owner's Manual pgs 205-206): CAVITY FUSE DESCRIPTION 1 10 amp (RED) Radio 2 15 amp (Lt Blue) Cigarette Lighter 3 10 amp (RED) Rear Washer Switch, Body Controller 4 10 amp (RED) Airbag 5 10 amp (RED) Lamp Out Module, Overdrive Switch, OBD II 6 15 amp (Lt Blue) Vehicle Information Center/Graphic Display Module Park & Side Lamps, Overhead Console Lighted Visor, Automatic Dimming Mirror 7 20 amp (Yellow) Body Amp, Cluster, Body Controller 8 20 amp (Yellow) Rear Wiper Motor, Flipper Glass Solenoid, Cargo Lamp, Trailer Tow 9 15 amp (Lt Blue) Brake Switch 10 10 amp (RED) Rear Window Defroster 11 10 amp (RED) ABS Module 12 10 amp (RED) Heater-Ventilation-A/C Control & Recirculation Motor 13 15 amp (Lt Blue) Hazard Switch, Turn Signal Switch 14 15 amp (Lt Blue) Spare 15 15 amp (Lt Blue) Spare 16 10 amp (RED) Right & Left Courtesy Lamp, Glove Box Lamp, Halo Lamp Cargo Lamp, Underhood Lamp, Dome/Read Lamp Right & Left Visor, Automatic Dimming Mirror 17 15 amp (Lt Blue) Radio Illumination, Tail Lamp, Graphic Display Module, Park & Side Lamps, Headlamp Switch, Body Controller 18 20 amp (Yellow) Spare 19 15 amp (Lt Blue) Passing Light 20 15 amp (Lt Blue) Radio, Heater-Ventilation-A/C, Vehicle Information Center 21 15 amp (Lt Blue) Power Outlet 22 10 amp (Blue) Airbag Module Turn signals are in the flasher and it is located on the driver side below the dash (where the buzzer is located). It is a cylinder type relay. You will find two, one for the hazzard lights and the other for the signals.

Which fuse ? Just to make sure you looked at the right one .
DISPLAYS fuse 10amp located in the I/P fuse block .
Do you know what DTC'S - diagnostic trouble codes are ?
DTC B3619
The HUD detects that the HUD change page switch signal circuit is low for greater than 15 seconds.
DTC B3634
The HUD detects that the HUD dimming signal circuit is low for greater than 15 seconds

Diagnostic System Check - Head Up Display
Install a scan tool.
Does the scan tool power up?
Go to Step 2
Go to Scan Tool Does Not Power Up in Data Link Communications
2
Turn ON the ignition, with the engine OFF.
Attempt to establish communication with the following control modules:
• Head Up Display (HUD)
• Instrument panel cluster (IPC)
• Powertrain control module (PCM)
• Driver information center (DIC)
• Radio
Does the scan tool communicate with the control modules listed above?
Your best bet , take it to a qualified GM service center .

On this website you find information (diagram, description and location) about fuse boxes in Cadillac XLR (2004 - 2005)

Cadillac XLR 2004 2005 fuse box diagram Auto Genius

The Heads Up Display (HUD) usually fails because of a spring that holds the mirror assembly comes unhooked or pulls through the plastic anchor hole. The HUD unit needs to be removed out of the dash for repair. Several people have epoxied a washer where the original hole was located with very good results. Takes between 2 to 3 hours to repair. Repair instructions can be found on several automotive forums.

If fuse check out. All electronics fail some goes out sooner than others; Once the HUD unit its out you have to replace it unless you electronic guru know about electronics and solder, go to the junk yard and get a replacement. New unit will cost an arm and a leg. I had the same car and my went out on me 3 years after, thank GOD it was still under the warranty. wish lot of luck finding use one.

If you peek down inside the windshield, you'll probably see the HUD is working. A common issue is that the adjustment spring will break, making the HUD invisible because it is adjusted out of range. The spring can be replaced by removing the cluster then the HUD unit.