The TJ Mirror Company auto dim / temp / compass mirror one month review

[CreepinDeth]

For thise interested, these are a dime a dozen in boneyards in countless GM vehicles, and on Ebay.

I put two of these Gentex mirrors in both my classic GM vehicles over 14 years ago for next to nothing. Auto dim, compass, temp, and map lights. Cost can be done for ~$50-$60

temp sensor is like $5
https://www.rockauto.com/en/parts/acdelco,25775833,,

 

[J.Pierce]

There are two ambient temp sensors - one for the PCM and one for the mirror. Did you reuse the PCM one for the mirror?

Andy

Yes, I got the sensor out of the suburban when I pulled the mirror.

 

[AndyA]

And so we come to the temperature. The temperature display has been inaccurate since the day I installed the kit. It displays a temperature that is consistently five to ten degrees warmer than all other temps I can cross reference to.

I think the bottom line here is that you should go back to them and tell them that it can be made to work properly by others so they need to figure out the problem and send you an updated temp sensor or mirror. They can easily bench test a combination for themselves before sending it.

Andy

 

[MikekiM]

I think the bottom line here is that you should go back to them and tell them that it can be made to work properly by others so they need to figure out the problem and send you an updated temp sensor or mirror. They can easily bench test a combination for themselves before sending it.

Andy

Maybe I have more money than sense, but honestly, I don't have the time, energy or inclination to fight with them. This is the world we live in now. You over pay dramatically and receive inferior product with zero quality control.

 

[MikekiM]

Interesting update..

I really had no plans to troubleshoot the mirror. Kind of felt like the money was spent, I made a few attempts to get it to work and didn't feel like haggling with the vendor to get it right.

Then I receive an unsolicited email from the TJ Mirror Company noting that this post had come to their attention, apologizing for the inconvenience and offering to help make it right. OK, so that's pretty cool. Although I don't have it working yet I am going to retract (or at least very much soften) my comment about overpaying, inferior products and zero QC. I lumped them into a category of shoddy merchants that indeed is all too popular in our world today, and that was wrong of me. The fact that they reached out to me to help is stand-up. My apologies to TJMC for stereotyping them.

They said that most customers typically see temps that are +/- two degrees. I could be totally ok with that but this week I saw a ten degree error while on the highway, so there's still something up.

TJMC offered to exchange my Double DIN unit for one that is just compass and auto-dim, likely due to my comments above about if I were to do it again, but truth told.. if they are willing to engage I would really prefer to get what I have to work properly, and that is exactly what I am going to suggest to them in my response.

So.. My review stands... The kits are complete and well done (albeit in need of a little more attention to the exposed harness around the windshield). The compass is great. The auto dim feature does exactly as expected. The temperature... let's see what happens. Shame on me for stereotyping before giving them a shot at helping. It would have taken just as much time to email them for help as it did to write my review. Lesson learned. Kudos to TJMC regardless where this ends up. Stand-up merchant for sure.

Stay tuned.

 

[AndyA]

Now that is what I like to hear. Andy

 

[tworley]

Another gntx user here. I got mine from an early 00s Tahoe for <$20 with the wiring. Works great. My only complaint after maybe 5 years of use is the readout is very very dim and I can barely read it.

 

[MikekiM]

Putting some year-end closure on this project. Hind sight being what it is, if I had the chance to do this over.. I wouldn't. Or, at least I would do it different. As often is the case, it was a bit of a impulse buy and if I could undo it, I would.

The temperature display has never been resolved. Auto dim works fine, as does the compass, and the larger size is worthwhile.

The vendor did try to make it right by offering me a few options of which I chose a replacement double din mirror. What I had. I offered that if it didn't work as expected, I would live with it and that's where I am.

Sadly the replacement they sent wouldn't mount to the windshield. As best as I can tell, the chamfer that is on the back side of the mirror and what slides over the mounting plate on the windshield is damaged. I can slide the mirror on the mount but once I tighten the set screw, the mirror pops off.

Overall the company was good to deal with. Responded to my emails and did try to make it right, but I gave up on it. I now have an extra double din, auto dim, temperature, compass mirror that is collecting dust and another in the jeep that displays ambient temps that are as much as ten degrees off what is published elsewhere.

Close the book on this as one of the only TJ mods I regret.

 

[kmbarreiros]

Putting some year-end closure on this project. Hind sight being what it is, if I had the chance to do this over.. I wouldn't. Or, at least I would do it different. As often is the case, it was a bit of a impulse buy and if I could undo it, I would.

The temperature display has never been resolved. Auto dim works fine, as does the compass, and the larger size is worthwhile.

The vendor did try to make it right by offering me a few options of which I chose a replacement double din mirror. What I had. I offered that if it didn't work as expected, I would live with it and that's where I am.

Sadly the replacement they sent wouldn't mount to the windshield. As best as I can tell, the chamfer that is on the back side of the mirror and what slides over the mounting plate on the windshield is damaged. I can slide the mirror on the mount but once I tighten the set screw, the mirror pops off.

Overall the company was good to deal with. Responded to my emails and did try to make it right, but I gave up on it. I now have an extra double din, auto dim, temperature, compass mirror that is collecting dust and another in the jeep that displays ambient temps that are as much as ten degrees off what is published elsewhere.

Close the book on this as one of the only TJ mods I regret.

To bad it doesn't have the home link or I would offer to buy it. I have older garage doors and my jeep is always garaged so that would be super helpful. Rather then have the remotes in the Jeep. I may look into the one with the home link and compass the price wasn't terrible.

 

[Dr. Internet]

In addition to the '06 LJR, we also own a '12 Grand Cherokee. It displays the temperature on the dash, between the speedo and the tach. It has been five degrees high since we bought the vehicle. The fix - just subtract five.

 

[MikekiM]

To bad it doesn't have the home link or I would offer to buy it. I have older garage doors and my jeep is always garaged so that would be super helpful. Rather then have the remotes in the Jeep. I may look into the one with the home link and compass the price wasn't terrible.

Thought about Home Link when I bought it but my house is all Smart controlled via Apple Home Kit, so the garage could be programmed to open Home Kit recognizes I am approaching home.

In addition to the '06 LJR, we also own a '12 Grand Cherokee. It displays the temperature on the dash, between the speedo and the tach. It has been five degrees high since we bought the vehicle. The fix - just subtract five.

Sure.. easy enough to do the math, but it isn't always off by the same amount so I have to look at my watch to see the temp so I am doing the math right. Waste of time.

I could have swapped out the current mirror with a single DIN.. just compass.. but I had hopes the replacement mirror would solve the issue.

I've wasted $200 in far worse ways.

 

[SkylinesSuck]

I wonder if an inline resistor would help correct the temp or if it would go the other direction.

 

[MikekiM]

I wonder if an inline resistor would help correct the temp or if it would go the other direction.

hmmmm.. I am open to ideas but that is beyond my pay-grade.

 

[SkylinesSuck]

Mine too, but I would grab a multi meter and go take some resistance measurements at different ambient temps. See which way the resistance goes with associated temps. If resistance goes up with decreased temps (I guess it goes the other way though), adding an inline resistor would trick it in to showing a colder temp. Trial and error to find the right one. And if resistance goes the other way, you could always use a different temp sensor that reads too cold and go from there. They also make variable resistance potentiometers (I think that's right?) so you can just fine tune it with a little screw driver.

 

[freedom_in_4low]

Putting some year-end closure on this project. Hind sight being what it is, if I had the chance to do this over.. I wouldn't. Or, at least I would do it different. As often is the case, it was a bit of a impulse buy and if I could undo it, I would.

The temperature display has never been resolved. Auto dim works fine, as does the compass, and the larger size is worthwhile.

The vendor did try to make it right by offering me a few options of which I chose a replacement double din mirror. What I had. I offered that if it didn't work as expected, I would live with it and that's where I am.

Sadly the replacement they sent wouldn't mount to the windshield. As best as I can tell, the chamfer that is on the back side of the mirror and what slides over the mounting plate on the windshield is damaged. I can slide the mirror on the mount but once I tighten the set screw, the mirror pops off.

Overall the company was good to deal with. Responded to my emails and did try to make it right, but I gave up on it. I now have an extra double din, auto dim, temperature, compass mirror that is collecting dust and another in the jeep that displays ambient temps that are as much as ten degrees off what is published elsewhere.

Close the book on this as one of the only TJ mods I regret.

Did you check the temperature reading on the mirror that won't stay mounted? That would at least tell you whether there's actually anything wrong with the first mirror.

 

[freedom_in_4low]

Mine too, but I would grab a multi meter and go take some resistance measurements at different ambient temps. See which way the resistance goes with associated temps. If resistance goes up with decreased temps (I guess it goes the other way though), adding an inline resistor would trick it in to showing a colder temp. Trial and error to find the right one. And if resistance goes the other way, you could always use a different temp sensor that reads too cold and go from there. They also make variable resistance potentiometers (I think that's right?) so you can just fine tune it with a little screw driver.

I hadn't seen this thread until now but as I read I wondered if there was a corroded connection in the circuit somewhere that was bumping the temperature reading up, if it's a Positive Temperature Coefficient sensor.

NTCs (negative temp coeff) are far more common in my industry but that may not be true in automotive. I figure you probably have the resources to tell which type they used for the IAT, ECT and the ambient sensor the PCM uses. I would think odds are high that whichever those are, this one will be the same. If it's NTC then that kills my corroded connection theory but it brings hope to your suggestion of adding some resistance to offset the reading.

 

[MountaineerTom]

Seems like I've seen adapters for mirrors that are too big for the button on the glass.

 

[MikekiM]

Did you check the temperature reading on the mirror that won't stay mounted? That would at least tell you whether there's actually anything wrong with the first mirror.

Candidly, I can't recall. I was a bit frustrated with the mirror falling off the windshield mount. Just put it aside.
I could and likely should do that. I'm not sure if the mirror side mount could be retro fit to replace the busted one. I put this back on my todo list.

I hadn't seen this thread until now but as I read I wondered if there was a corroded connection in the circuit somewhere that was bumping the temperature reading up, if it's a Positive Temperature Coefficient sensor.

NTCs (negative temp coeff) are far more common in my industry but that may not be true in automotive. I figure you probably have the resources to tell which type they used for the IAT, ECT and the ambient sensor the PCM uses. I would think odds are high that whichever those are, this one will be the same. If it's NTC then that kills my corroded connection theory but it brings hope to your suggestion of adding some resistance to offset the reading.

I couldn't say would kind of sensor it is.

Its blue.

I have two of them now. The sensor was the first thing the vendor replaced.

Seems like I've seen adapters for mirrors that are too big for the button on the glass.

So I am not sure that would help. I just deleted the pictures I had of the underside of the mount. It's the correct size. There is a mated dovetail that slides on, but once the set screw is tightened it pops off.

 

[Rockytop]

I was considering installing the TJ Mirror Co mirror but didn't like the cost. I started researching what others have done on internet. I ended up going with used GENTX 453 Mirror. It comes with several models. I chose to go with the unit that has the homelink, compass and ambient temperature readout. It comes with green display to match the rest of TJ dash lights. It has auto dimming feature. On eBay you can find these mirrors in very nice shape. Connector w/pigtail and wire harness cover included. I had to match this mirror with Nissan factory temperature sensor. Nissan sensor is calibrated to be used with this mirror. I tried using jeep sensor and the temperature reading was way off. (don't use Jeep temp sensor that's located on passenger side in front of radiator) Also sensor that's on the driver side near radiator will also give you false temperature reading. I thought something was wrong with the mirror.
My 2005 TJ did not come with the factory wire harness that runs on top of the dash under the vent cover. I made my own harness and ran wires for power and to the sensor in front. I located the sensor up front under the left front fender near the orange running light. Temperature is accurate within 0-2 degrees compared to my phone info. This entire setup cost me $100 bucks and it provides more features then new mirror.

 

[MikekiM]

I was considering installing the TJ Mirror Co mirror but didn't like the cost. I started researching what others have done on internet. I ended up going with used GENTX 453 Mirror. It comes with several models. I chose to go with the unit that has the homelink, compass and ambient temperature readout. It comes with green display to match the rest of TJ dash lights. It has auto dimming feature. On eBay you can find these mirrors in very nice shape. Connector w/pigtail and wire harness cover included. I had to match this mirror with Nissan factory temperature sensor. Nissan sensor is calibrated to be used with this mirror. I tried using jeep sensor and the temperature reading was way off. (don't use Jeep temp sensor that's located on passenger side in front of radiator) Also sensor that's on the driver side near radiator will also give you false temperature reading. I thought something was wrong with the mirror.
My 2005 TJ did not come with the factory wire harness that runs on top of the dash under the vent cover. I made my own harness and ran wires for power and to the sensor in front. I located the sensor up front under the left front fender near the orange running light. Temperature is accurate within 0-2 degrees compared to my phone info. This entire setup cost me $100 bucks and it provides more features then new mirror.

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Are the sensors interchangeable? Do you have details on the sensor you used?

I've tried two so far and neither is any better.