Submitted By: 85_Ranger4x4

Difficulty: 3 out of 10

Time To Install: Half a day.

Disclaimer: The Ranger, The Ranger Staff, nor the original poster are responsible for you doing this modification to your vehicle. By doing this modification and following this how-to you, the installer, take full responsibility if anything is damaged or messed up. If you have questions, feel free to PM the original poster or ask in the appropriate section of The Ranger forums.

Brief Explanation: How to install a compass/thermometer mirror into pretty much anything. Some of it is kind of vague, this details the installation into my 1985 Ford Ranger so it will vary for 2011 but this should at least get it working, you may have to figure out some details for your truck on your own.

Tools Needed to Remove from Donor:

  • T20 Torx
  • Wire Cutters
  • Knife (optional)
  • 5/16 nutdriver (or similar ratchet etc)

Tools Needed to Install:

  • T20 Torx
  • Wire strippers/crimpers
  • Whatever it takes to remove your grille (standard Phillips screwdriver for me)
  • Tinsnips or someway to notch the trim along the top of the windshield (mine is metal)
  • Pliers

Parts Needed:

  • Mirror
  • Ambient temp sensor
  • Wire. You will have two pigtails you will need to connect plus a wire to splice and run a ground.
  • Wire connection supplies (butt connectors, heat shrink and/or solder depending on how you prefer)

Step 1. Source Your Mirror:

I found mine in a ’97 Chevy Tahoe. A T20 Torx will loosen the setscrew to allow you to remove it. You may want test fit into a vehicle similar to yours at the JY and make sure the mounting boss is the same size. My mirror is a model GX177.

Get as much of the pigtail that plugs in the back as you can too.

Remove the grille from the donor vehicle, on my donor the ambient temp sensor was mounted down low in the center of the grille. Get as much of the harness as you can, you can get quite a bit of it by cutting zipties and tape.

Step 2. Prep Your Truck:

Remove your grille and find a place on the front of the radiator support similar to the donor where you can install temp sensor so it will get good airflow. DO NOT try to bend the metal mounting tab, it is made of a weird steel and will snap rather than bend.

Mount the sensor and route wires thru the radiator support towards the firewall. Test fit the grille to make sure nothing is in the way, I would leave it off until you know everything works though.

I broke the tab off of my sensor so I just ziptied it in place for now, it seems to work well as it is.

Remove trim along the top of the windshield and up the drivers side (DS from here on out) A-pillar. 3 phillips screws on both trim pieces for me.

For the upper windshield trim, find the center and make a small notch to allow the wiring to pass into the cavity inside the trim. Mine was metal so I did two small snips with tinsnips and bent it back with pliers.

To remove the lower kick panel remove the two Phillips screws retaining the kick panel and loosening the front aluminum trim screw along the floor will help too.

Step 3. Swap Mirrors:

Remove your old mirror, mine used the same T20 torx as the new one but it was a replacement one. Install your new mirror on your windshield.

Step 4. Wire It Up:

Ok, the wiring schematic for mine (most seem pretty much the same) is as follows:

My truck does not have auto dimming mirrors as an option, if yours did and you get them to work please let us know how.

Now, Run Your Wires.

Pin 1: Make sure the 12v power source is hot with the key and is fused.

Pin 2: I ran the ground wire to the big cab ground to the right side of the fuse panel. Shown as G202 in Figure 1.

Pin 3: The mirror needs to know when your truck is in reverse so it doesn’t auto dim when you are backing up. It needs to be wired into your backup lights. For my truck, this connector (C156) comes thru the frame behind the DS inner fender from the transmission. Do not remove the other two wires, they were not just not used for my truck. Note the mirror only gets power when the truck is in reverse. Once I disconnected it I was able to pull it out the bottom and work on it under the truck to have more room. Splice into the wire that is hot only with the truck in reverse and reconnect the connector.

Pin 4: Not used

Pin 5: Not used

Pin 6: Connect to green wire on temp sensor

Pin 7: Connect to Black/white wire on temp sensor

I have a big grommet in the firewall to get the temp sensor wires thru, that is going to be another vary by truck thing.

Now for the big moment of truth, see if it works. The compass may only display “C”, if it does it will need calibrated, don’t worry about that now. Use “Compass” button to show the compass, “Temp” button to show the temp. Hold on temp and you can toggle between C* or F* degree readings.

Step 5: Reassembly

Put the grille back on. Tape the wiring inside the cab to keep it in one cohesive bundle so you are not herding cats trying to keep it all together. Install the upper trim taking care to keep the wiring from interfering with the screws or getting pinched. Reinstall the A pillar trim keeping the wiring in the handy built in notches provided:

Reinstall kickpanel with its two screws and tighten up the aluminum trim screw.

Step 6. Calibrating:

Go find an empty parking lot. Drive in a circle a couple times, generally three circles and it should start saying compass stuff but it will be off. Give it a couple more turns and and it should zero in and be fairly close. They are not an exact navigation aid but are pretty close most of the time.


Check out the original submission: Compass Mirror Install

More Articles: