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Installing a Gentex Compass/Temp/Auto-dim mirror

Tony_SS

NAXJA Supporting Vendor
Location
Washington MO
Once I had one of these mirrors I got hooked. They are very well made, a bit wider and thicker than the factory one. The auto-dim is nice but the compass and temp is the real reason to get one.

These mirrors can be found in almost any GM 96 and newer, I think. Mostly they'll be in full size trucks but can even come from Saturn Vue's so check the yards. I got the mirror for $40 with a temp probe and connector. I elected to get a install kit off ebay for another $50. This included everything shown with my mirror here. It made the job really easy and saved a lot of time, but you can use any 18-20 gauge wire.

4 wires
switched power
ground
2 prob wires

Here's what I started with (speedo gear not required!)

IMG_1924_zps88f7cbcb.jpg


I mounted the prob behind the bumper and grille in the center to keep it clean and away from engine bay heat.
IMG_1940_zps1b143d03.jpg


Run those 2 wires from the prob to the mirror. I poked a new hole through the firewall. I'm going to use the same hole to run my amp power wire later.
IMG_1942_zpsc65509da.jpg


This pic, these are the other wires that go to the mirror. The trick is to hide them. Make like you're flossing your teeth to get them behind the dash like shown. From there, run them up your a-pillar.
IMG_1934_zps4f3bd7ae.jpg


Not shown, but you need switched power and a ground going to the mirror too. I just tapped the red and black wire coming from the 12v accessory.

From the a-pillar to the headliner, no wires should be showing.
IMG_1938_zps84e6aec8.jpg


The mirror will use your existing mount, just screw it on. Use the plastic guide to cover the wires coming down from the headliner.
IMG_1937_zps26850e11.jpg


Soon as you plug it in, it should work. But you may need to circle the lot to get the compass to register.
IMG_1948_zpsbf3c4af9.jpg
IMG_1949_zps8fe0eed8.jpg


IMG_1953_zps86aa3009.jpg
 
I always thought auto dim was lame: I mean who is to lazy to flip a switch.

After intalling one, I feel like I was missing out
 
Thanks for posting this. I've been wanting to do this for a while on my '01 XJ and now I have a good and easy write-up that lays it out.

I'm not sure I'll be able to hit up the salvage yards and may just buy the whole kit (wires and all) for a bit more money just to save my time and hassle of trying to track it all down on my off-time.
 
The wire kit is pricey. $55 plus shipping. But it comes with everything but the mirror. The wire itself is crosslink wire, and appears to be great quality. To me it was worth the money and I just had to worry about getting a comp/temp mirror.
 
We installed one of these mirrors on my daughter Mira's XJ. Very straightforward, and I love the functionality. I had a similar mirror on my old '05 LJ.

We have another Gentex mirror/install kit waiting for my younger daughter (just turning 11 yrs. old) when she gets an XJ.
 
some good info in this thread on jeepforum- some of it I figured out and posted; some of it I wouldn't have got as far as I did without the work of others - somewhere in there is the part numbers of the connectors, I believe they are the same 7-pin MagnaDonnelly and Gentex

http://www.jeepforum.com/forum/f9/c...-swap-detailed-lots-o-pics-952705/index9.html

BTW I would run the wires down the pass side because then you can tap into the connector for the overhead console & get power there, and also that is where the factory wires for the outside temp sensor terminate if you get a mirror that has temp display like I did you don't have to actually run the wires through the firewall, just use a factory temp sensor and plug it into the connector behind the front bulkhead.

I like my setup, I have temp and compass in mirror as well as map lights that come on with the dome lights. Only problem is that it reboots every now and then. I also have my phone plugged into the USB port on the front of my JVC head unit and the power for my mirror is coming from the HU adapter (because when I first hacked it in I hadn't figured out the connector for the OHC yet) and my phone sometimes drops out of "vehicle mode" making me think that that is where the problem is... radio never shuts off though. Maybe I need a capacitor?
 
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FWIW, or Gentex mirrors were a new install. I have the part numbers for the wiring, and the installation instructions at our garage/shop. I can provide them in about a week (won't be up there until then), if anyone needs them.

EDIT: I just found the install instructions in my file.

Part numbers for the harnesses:
* 50-GENK2A (7-pin Auto-Dimming Mirror)
* 50-GENK5A (7-pin Auto-Dimming Mirror with Compass)
* 50-GENK21A (7-pin Auto-Dimming Mirror with Compass and Temperature)

Install instructions are an 11-page document.
 
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BTW I would run the wires down the pass side because then you can tap into the connector for the overhead console & get power there, and also that is where the factory wires for the outside temp sensor terminate if you get a mirror that has temp display like I did you don't have to actually run the wires through the firewall, just use a factory temp sensor and plug it into the connector behind the front bulkhead.

You know, I did find an unplugged connector dead center behind the core support of the front bumper. Are you saying that's where the factory temp sensor would be? I also found 2 unplugged harnesses along the driver side of the of the fender well under the hood. If I knew about the factory harness a little better I would have tapped those for sure.
 
You know, I did find an unplugged connector dead center behind the core support of the front bumper. Are you saying that's where the factory temp sensor would be? I also found 2 unplugged harnesses along the driver side of the of the fender well under the hood. If I knew about the factory harness a little better I would have tapped those for sure.

Yes, the plug behind the front bumper is for the factory overhead console OAT sensor. N8N_98xj is correct this harness terminates in the lower kick panel on the passenger side by the fuse junction box. If you look on some of the write ups for overhead console installs, they tell you which plug it is.

I love my Gentex mirror. I got it out of a '00 Cadillac, so it show temp and compass at the same time. For those looking to do this mod, beware, some Gentex mirrors only have a compass feature and not compatible for a temp sensor. (ask me how I know haha) I got my full set up from PNP for 5-6 bucks, Mirror, OAT sensor and a OAT pig tail. I used that same write up from Jeep forum, he does an awesome job explaining how to do it!
 
Well shoot! I would have tapped in there for the sensor. Oh well. I need that hole through the firewall for some 8ga wire to power my upcoming amp install. :)

YES, get the DUAL display mirror that shows both the temp and compass at the same time. It's better than toggling to see the readouts. Also buttons on the front should say COMP / TEMP so you know the mirror and do both.
 
Yep, for a lighted mirror with compass and temp run four wires down the pass A-pillar for temp and switched power, and two to the front dome light for constant power and dome signal. Only thing left if you want to do it is another wire to the NSS for reverse dimming override.
 
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