I have embarked on installing an auto-dim Gentex in my IQ since my OEM mirror started shedding silver lining around the edges. An auto-dim mirror comes as a factory option on Cygnet, so I thought it should be a simple plug-and-play in IQ. Now, Gentex makes a whole range of mirrors with all kinds of features. The one I settled on is GNTX-221, which comes with built-in LED lights, which is a highly desirable feature in the dim IQ. Depending on a configuration, it can also have any or all of compass, temperature display, and an auto-dim controller for external mirrors.
While there, I figured I might as well install a dashcam with a rear camera module. I went with VIOFO A129 PRO Dual Channel Ultra 4K and a VIOFO HK3ACC Hardwire Kit.
After some search, I was able to get a mirror from ebay for about $60 that came off a ‘01 Lincoln Continental, item 010404, that has a compass (an external add-on that mounts on the mirror stem and looks like a cancerous growth) and an door mirror dim output (not needed in IQ). Note that all versions of this mirror are marked as 221, so you have to be really careful whether you are getting the one with temperature, compass, or both. You can tell the compass by an external module on the mirror stem, and the versions that have both temp and compass have a double-tall LCD display.
After a test, I was able to confirm the Gentex mirror snaps straight into IQ’s mirror mounting bracket on the windshield.
However, there are 3 problems:
1. The compass display is green, while the rest of IQ illumination is orange.
2. The door pin on the mirror expects V+ while the dome door wire is normally V+ and goes to GND when the door is open (because Toyota!).
3. The mirror has a constant drain of about 0.5A, which can eventually kill your battery (https://gmlongroof.4umer.com/t11675-...ass-mirror-mod)
You can probably get a version specific to Toyota to solve #2, but #3 still requires a workaround. For this installation, I have reversed the door wire voltage with a transistor and solved the drain problem with a timer relay. I have also changed the color of the LCD by replacing the green filter with an orange film.
Let’s start with a parts list.
2N3906 transistor, 1k ohm resistor and 3-4 diodes.
Universal Gels Lighting Filter Kit
3m velcro (can get a few smaller packs from HomeDepot or Lowes)
3m double-sided heavy-duty mounting tape
You favorite sticky tape to wrap around sharp edges. I’m using some Grace Viacor sheathing tape which I think Gorilla brands as a waterproof seal and sells for twice the price https://www.amazon.com/Gorilla-Water...dp/B08126M2R4/
Strapping tape (used to hold wires on the headliner)
I also recommend getting an assortment of Molex H-DAC 64 connectors from DigiKey – they make life so much easier!
They can be crimped with this:
Optionally, you can also get a cover for the mirror cable - search for
‘Gentex 50-9010079001M Short Rearview Mirror Black Wire Cable Cord Cover Plastic’ on ebay. It requires some shortening to fit between the mirror and the headliner though.
The easiest part is changing backlight color on the compass. For this, we need to take the mirror apart. Here are a few videos to give you an idea of what we are dealing with. The bezel can be undone by stuffing a gift card into the seam between the mirror and the bezel and running the card along the edge of the bezel. Make sure to not pry on it too hard, as the plastic can be brittle from the age and can crack (can be glued back together with JB weld).
Once inside, unclip the compass module and replace the green color filter with two layers of orange Universal Gels Lighting Filter Kit (one layer is too bright). I’ve used a tack glue to hold the gels in place so I can easily change them if I need to, but a dub of super glue would do just fine. Make sure to not touch the surface of the films – they mark and bend very easily.
Next is wiring the mirror. A pinout for the mirror is this (https://wranglertjforum.com/threads/...-wiring.14397/ )
Pin#1: Ignition – Ignition source when key is in the ON position
Pin#2: Ground – Chassis Ground
Pin#3: Reverse Over-ride – Connected to reverse lights. To disable compass when car is put in reverse for better visibility
Pin#4: Temp. + -Temperature probe + Or External Mirror control +
Pin#5: Temp. - - Temperature probe – Or External Mirror control -
Pin#6: Door switch – (Normally open) Turns on mirror LED lights
Pin#7: Battery – Constant 12v
Just in case, here is a compass calibration guide (basically, you need to select a correct zone and drive in circles several times).
Since we have Battery, Ground, and Door wires available on the dome connector, we need to find and get ACC and Reverse from the floor kicker panel somewhere close to the dome light.
Start by disconnecting the battery as you will working close to the air bags!!! While routing new wires, make sure to stay away from any air bags and airbag wires/connectors.
For ACC, you can either tap into the door mirror control panel connector or into green wire on one of the floor blue connectors, see the pictures (two of the pictures are from Scion interior light kit guide and Rostra cruise control guide). For Reverse, you can tap into red-white wire on one of the computer connectors.
Start by removing the left kick and knee panels, left A and B pillar covers, left driver’s grab handle, sun visors and its mounts, and the dome light. You can use a show manual from this forum to get an idea of the exact procedure. You can run the new wires alongside the dome light in a separate split tubing. Alternatively, you can route them through the existing tubing; it’s a chore, but they do fit! This would also be a good time to install OEM Interior Light Kit if you haven’t done so already.
Next, assemble the timer relay and the transistor part of the circuit. Timer is used to feed battery voltage to the mirror and disconnect the voltage after a set time to prevent the mirror from draining the battery. The timer relay is ON as long as either the door is open or ACC is ON. The transistor is used to reverse Toyota Door wire in the dome light from 12V->GND into GND->12V used by the mirror. This wire is used to automatically turn on the mirror lights when the door is open, and to trigger the timer (in addition to ACC) as described above. The transistor and diodes are then glued with a double-sided tape to the relay.
The timer/transistor assembly is attached to the roof using a 3M mounting Velcro tape. There is plenty of space between the headliner and the roof to the right and the left of the dome light. Make sure to wrap all sheet metal edges that rub on the wires with some kind of a protective tape.
The dashcam power adapter is mounted in a similar way to the other side of the dome light. I had to shorten and re-solder the excessively long cables on both sides of the power adapter.
Next step is to make a junction block to connect it all together. I have used a PCB to solder wires together. The PCB and the wires on the reverse side were then covered in a clear epoxy.
The final tricky part is to jam it all next to the dome light and verify that everything works as designed!
The rear dashcam is routed along the dome harness to the foot kick panel. From there, route to the back, then up, then through the liftgate boot in the liftgate itself. The cable that comes with camera is just about the right length to reach a location next to the motor of the rear wiper.
The caveat is that when mounted this way, the camera faces a little up as opposed to straight back. I plan to remedy this by making a 45 degree wedge that I will place between the camera’s base and the windshield.