Question for anyone with a factory Gentex compass / temperature mirror

Chris

Chris

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I just finished installing my Gentex 221 (GNTX-221) compass / temperature mirror in my Rubicon. It plugged right in, and everything works as it should.

However, upon plugging it in, I notice that the LED lights on the underside of the mirror (reading lights I guess they call them) will not turn off even when pressing the buttons on the mirror to turn them off. They just will not go off no matter what, unless I turn the interior lights on (the dome lights) using the switch on the turn signal stalk.

I want to say this has something to do with my doors being off, but I also have fuse #4 pulled, so the interior lights in the vehicle don't come on when the doors are removed as it is.

Any idea what I might be missing here?
 
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If you want me to try and duplicate anything for you just let me know. I can also PM you my cell # if you want to speed up troubleshooting.
 
CodaMan said:
My doors are off, I have fuse #4 pulled and my reading lights work as they should.
Click to expand...
So your reading lights don't come on at all when you put the key in the ignition or anything?

I'm trying to figure out what is wrong here. I check the pin outs on the factory wiring harness going to the mirror, and the pin out for the mirror itself. Everything matches up perfectly, so I'm not sure what's going on with this. The mirror works, the dang lights just won't go off.

I'm not even sure how to troubleshoot this.
 
They only time they come on is when I push the button ... no mater if the key is in/out/on/started ... Doesn't make a difference if lights are on/off or what position the dome switch is in.
 
CodaMan said:
My initial thought would be a bad mirror.
Click to expand...

I'm thinking the same thing. However, this mirror was brand new in the box (NOS from a Ford dealer apparently), so that has me skeptical.

Do you know what model your mirror is? Mine says GNTX-221 on the back. The pin out on this mirror matches the pin out coming from the vehicle, and on some of the other TJs I've seen with the factory mirror, it was a 221 as well.
 
CodaMan said:
GNTX-221
Click to expand...

Okay, so then all that can explain this is a bad mirror I guess.

Also, all my mirror says is "C" in the digital read out. No temp, no compass.

When you start yours up, does it immediately say the temp and direction on it? Or do you have to drive around for a while for that info to register?
 
CodaMan said:
I only need to turn the key to the ON position to see temp and direction.
Click to expand...

Okay, so something is up then for sure. Mine just says "C" and that's it.

I got the factory temp sensor plugged in behind the grill (it's a brand new Mopar unit as well), I got the factory Mopar wiring harness brand new on Amazon, and I got the GNTX-221 mirror brand new as well.

It's got to be the mirror though.
 
CodaMan said:
Do you have another Jeep around you can troubleshoot with?
Click to expand...

No, but now I'm looking at the mirror and I see an issue.

My mirror looks like this:

s-l1600.jpg


The TJ mirrors appear to look like this:

s-l1600-1.jpg


You see the difference right?

Mine only has one line to output numbers on, whereas the other one has two lines, so it can have the temp on bottom and compass on top, all at once.

So this is odd...
 
I was thinking the “C” meant calibrate. Found this on another forum. Doesn’t help with the lights though.

1. You depress and hold BOTH maplight buttons for 6-8 seconds. A number appears in the compass window. That number is the Zone that the mirror is calibrated for. Mine was set for Zone 8, which is the factory default setting. Zone 8 is the proper Zone for me here in Florida.

If you want to change the Zone, press the right maplight button to go up, the left button to go down. I believe that there are approximately 14 zones across the USA.


2. Continue to hold BOTH buttons till the number disappears and a "C" appears. That "C" is CALIBRATE.

I drove slowly around in a tight circle. Two "laps" did the trick. The "C" disappeared, and a compass point appeared. The mirror is now performing flawlessly, "as advertised"
 
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jchadscud said:
I was thinking the “C” meant calibrate. Found this on another forum. Doesn’t help with the lights though.

1. You depress and hold BOTH maplight buttons for 6-8 seconds. A number appears in the compass window. That number is the Zone that the mirror is calibrated for. Mine was set for Zone 8, which is the factory default setting. Zone 8 is the proper Zone for me here in Florida.

If you want to change the Zone, press the right maplight button to go up, the left button to go down. I believe that there are approximately 14 zones across the USA.


2. Continue to hold BOTH buttons till the number disappears and a "C" appears. That "C" is CALIBRATE.

I drove slowly around in a tight circle. Two "laps" did the trick. The "C" disappeared, and a compass point appeared. The mirror is now performing flawlessly, "as advertised"
Click to expand...

I'll have to at least give this a try to see if it gets rid of the "C" and gives me a temp read out or compass read out. Thanks!
 
The other thing I saw is that they stay on similar to modern convenience lights and then turn off after a time delay when the ignition has been turned off. Have you tried turning the ignition off and waiting 30-60 seconds?
 
jchadscud said:
The other thing I saw is that they stay on similar to modern convenience lights and then turn off after a time delay when the ignition has been turned off. Have you tried turning the ignition off and waiting 30-60 seconds?
Click to expand...

Yep, tried that!

CodaMan said:
My mirror looks like the 2nd pic.
Click to expand...

I got screwed! I went back to look at the eBay auction I won. It says GNTX-221 in the title, in the add, and it even shows photos of the back of the mirror with "GNTX-221" imprinted on it.

I went out just now to look at my mirror, and it has GNTX-177 imprinted on it, and a totally different part number as well!

So in other words, I bought the right mirror, but the seller sent me a totally different mirror!!!

I guess that explains a lot. Ugh.
 
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