Heated Mirrors for the Si

[squiggy]

So I was doing some browsing on CHH's website and noticed that the EX-L has an option for heated mirrors and was debating doing a swap. As I was comparing part numbers I cam across this for the Si itself:

76253-TR0-305 MIRROR SUB-ASSY., L. (COO)(FLAT)(HEATED)

The part number is actually different than that of the EX-L. There is no indication that any other part has heating capabilities, though.

Could it really be as simple as swapping out the mirror? Is the wiring already in place to interact with the defrost button? Or does it really need a whole new sub-assembly and would the wiring of the Si even support the heating capability of the EX-L?

 

[bigbossin]

Installing heated side mirrors is not a project for the faint-of-heart, but for someone familiar with tearing into car bodies, it shouldn't be too hard either. As with any DIY, do anything here at your own risk. I'm not a trained mechanic or electrician, I'm not going to promise this won't set your car on fire or kill you. You have been warned.


So far I've only done this install on the driver's side and I haven't yet installed a tap on the rear defroster control line. It works when I test manually, but that's all that I can promise at this time. The instructions are based on the assumption everything will go to plan as I finish it up. I'll update this as I learn and do more.


Parts needed:
76203-TR0-A31 Mirror sub-assembly, right (heated) - Honda OEM part
76253-TR3-A31 Mirror sub-assembly, left (heated) - Honda OEM part
18 Gauge stranded wire in at least 2 colors (4 colors recommended, including yellow, white, and blue or black)
12 volt automotive relay and socket assembly, minimum 10 Amps capacity. This relay is overkill, but it's cheap enough and it worked for me:
Amazon.com: A2C 775 Universal Automotive Relay: Electronics
Bussman add-a fuse
Amazon.com: Bussmann BP/HHH ATM Add-A-Fuse: Automotive
A number of Wire-to-wire splicers or connectors of your favorite type
4 locking disconnects (minimum, more is recommended in case of errors)
Amazon.com: American Terminal E-FMR250N-100 22/18-Gauge Economy Nylon Fully-Insulated Male Quick Disconnects: Car Electronics
Some sort of tap for 22 gauge wire. This might work, though I haven't tried it:
Amazon.com: 3M 3MT-R-100 22-18 Gauge T-Tap: Automotive
Electrical tape
Split loom tubing 1/4-1/2 inch diameter (optional but recommended for clean, professional-looking install)
Zip ties


Estimated cost - $50 to $75 before shipping, depending on what you have on hand


Tools:
Wire stripper
Crimper (optional)
10mm socket and rachet tool, long extension recommended
Medium Philips screwdriver
Small slotted screwdriver
Ice cube tray (optional, for keeping track of screws)
Rag or old towel


The Concept
The Honda wiring diagram for the heated side-view mirrors shows the mirror heating elements are controlled by the same button that operates the rear-window defroster, but other than that, the circuitry for the heated mirrors is completely independent of anything else.


In Honda's design, a relay in the under-hood fuse/relay box is used to turn on the heating elements. For models where this feature is not factory-installed, the relay, wiring, and relay contacts don't exist. There is also no real reason the relay has to reside in the engine compartment since power is much lower than the rear window defroster (7.5A fuse is used on this circuit). Mounting a relay under the dash removes any need to penetrate the engine firewall and run additional wires in the engine bay.


Additionally, wiring for this is not included in any part of existing wiring harness. All wire will have to be new-run. If you're running wire to the mirrors, you might as well run an additional pair so you can install side-mirror turn signals at a later time if you want.


In my opinion, the biggest challenge in this process is making the transition from the door to the body of the vehicle.


Preparing for the install
In the process of this install, You'll have to do a substantial teardown of the door, including completely removing the side mirror assembly from the door


You'll also remove the dash lower panel (under the steering column), the dash subassembly visor (above the steering column), dash center lower panel (where the AUX input and power connector are located), drivers front door sill trim and trunk release cover, and the driver's kick panel. There may be additional console parts that have to be removed on the passenger side, so far I've only completed the driver's side.


Door sill and kick panel
You may not need to remove the door sill trim and kick panel, but I found it useful when looking for a place to ground my circuits. A steel bolt into the frame behind the trunk lock was for me a handy place to ground my circuits.


The lock cover comes off quite easily with the help of a flat-bladed screwdriver at the base. This reveals a Philips screw which you'll want to remove. Removing the lock cylinder is a bit of a trick, I'm not entirely sure what I really did to release it. I used a flat-bladed screwdriver to pry up from the base and


simultaneous depress it's latch plate. While doing that, I inserted my key into the cylinder and attempted to turn it past its normal limits. Lifting the cylinder and depressing the latch plate allows a catch at the base of the cylinder to slip out of it's normal locking slot. There is a tab at the top of the lock cylinder, when it is turned enough past its normal limits it lines up with a notch in the cylinder hole. When those align, it should then pop out fairly easily.


Once the lock cylinder is out, the door sill should lift out if you pull on it a bit. Behind the location the lock cylinder was you'll see the bolt I used as a grounding point.


The kick panel is immediately in front of the door sill. You'll need to pull the door liner out a bit to be able to release the kick panel. There's also a plastic plug at the front of the footwell that helps secure the kick panel, this comes out quite easily with a little prying from a slotted screwdriver. With those two items removed, the kick panel should lift out.


Next pull the lower dash cover to remove it. You'll need to disconnect the VSA button as well.


Running the control circuit
Pull carefully on the dash subassembly visor (immediately above the lower dash cover, includes driver's air vents) to release it. Like the lower cover, it is only secure with snap-locks. Disconnect the eco-mode button and hazard lights to be able to remove it.


To remove the center dash lower panel (where the AUX and power connector are), feel for two screws at the top. Remove these screws and pull the panel from the bottom. When it comes free, disconnect the AUX and power connectors and set the panel aside.


Reach behind the HVAC control panel and find the plug, there's a catch you'll need to depress to pull it out. Pin 6 on this plug is the one you'll want to tap with a t-connector or similar connector. The idea here is not to cut the wire but to make a T off of it so the rear window defroster button will also operate the relay for the side mirrors.


You'll want to run a wire and optionally a split loom wire tubing run with it. It is easiest to run this up to the right of the steering wheel through space opened up with dash subassembly removed and route it on behind the steering column assembly to the space behind the under-dash fuse/relay panel.


Wiring the door
Measure out two pairs of wire per door (4 wires per door), each wire long enough to reach the area around the under-dash fuse/relay panel. Use electrical tape to tape these at one end so they can easily be pulled together.


To remove the front door panel, you'll need to start by using the slotted screwdriver to release a catch and remove a panel behind the inside door opening handle. Behind this panel is a Philips screw. Remove the screw.


Carefully use a small slotted screwdriver to pry up the switch panel which has all the window and door lock controls. There is a small slot at the front to insert the screwdriver in. Lift straight up, try not to pry or you may cause damage. The panel should snap out. You'll have to disconnect the wiring connectors. One is simple, with a tab you depress and then pull. The other one has a latch, you may need to use the small slotted screwdriver to start prying this latch up to release it.


Behind the switch panel is another screw, remove it.


Pull the door panel from the bottom, it may be difficult to get the first snap to release. Pull the bottom and up the sides as these snaps start to come free. Lift the panel up to remove it from the door frame. The door handle is held in place with some snaps, if it doesn't immediately come free, feel around the


inside of the door handle for these snaps and press them to free the door panel entirely.


In the upper right corner of the door is a rubber grommet, pry this loose with a small flat-bladed screwdriver and peel back the plastic lining. Be careful, whatever they use to hold this in place is nasty, sticky, and likes to get on everything. Have a rag handy.


Disconnect the wiring harness that goes to the mirror and push its zip-tie plug out.


Use the 10mm socket, extender, and ratchet to loosen the 3 nuts holding the mirror in place. These are visible through holes in the door panel. Be very, very careful that you finish removing the nuts by hand and DO NOT drop them into the door frame. I dropped one and thought I was never going to recover it. It took all the creativity I had to figure out a way to get it out.


The mirror has a snap that has to be pressed down to fully remove it from the side. Be sure to carefully feed the wiring out with it.


Once the mirror is free, remove the one screw on the bottom retaining plate/seal and take that plate off. Remove the mirror itself by pry up from the bottom with a flat-bladed screwdriver, there are two snap latches to release on the bottom, then pull the bottom forward and up to release the mirror. There is a sticky material on the back of the mirror and it may take quite a bit of force to pull it upward.


Look inside the mirror, existing wiring will run down a tube to the bottom of the mirror. Push your set of new wire into that tube. It should come out the bottom with little resistance. Feed it into the existing split loom tubing for a clean run. Pull most of the wire through, leaving enough to work with. If you are not installing the turn signals at this time, tape that pair to the inside of the mirror, looping around so you have something to work with later.


I recommend that one of the wires for the mirror heating element be colored yellow, it will make things a bit easier to understand when connecting the relay later. Crimp the flat locking terminals on the wire for the mirror. Before installing the new mirror be sure to attach these terminals to the connectors on the mirror. It doesn't matter which wire goes on which connector. Install the mirror by reversing the process of removing the old one, press in hard - the motor adjustment assembly seems quite resilient, despite feeling fragile.


Pull any excess wire, but don't pull it tight, the mirror still needs to be able to move.


Reinstall the mirror assembly on the door, reversing the process you used to remove it. Be careful how you feed the wires in so that you don't run them across the track the window runs in when it is lowered.


Estimate what part of your wire assembly will be exposed as it runs from the door frame to the body and wrap that length, plus some extra on either side, in black electrical tape.


Open the door wide, reach in the gap between the door and frame where the existing wire runs in a sealed rubber tube. Push the edges of the door side of this rubber tube assembly in to release it from the door.


Run the wire through the now open hole, I recommend keeping it at the bottom of the hole. Once you've run your wire and are happy with how it runs inside the door, reinsert the rubber cover. You'll likely have to pull it from the inside as well, if should mold itself around your wire without too much difficulty.


The seal on the body side isn't so easy. Open the door wide and pry it via the hard plastic nubs from the top down until it releases. You'll have to close the door slightly to pull it all the way out. Run the wire into the body of the car from the bottom of this hole as well. You should be able to reach inside the car all pull it through pretty easily. Be sure to leave enough slack for it to easily work in the door frame, ideally your run should parallel the exist rubber tube.


Reinsert the rubber-covered wiring assembly in the body of the car, you will likely have to fully open and partially close the door several times to get everything inserted properly. This will not fit as cleanly as the door side, but you should be able to seal the upper portion well and the lower portion fairly well despite the added wires.


Take a moment to reassemble the door, test the driver's window to ensure it lowers properly, adjust the side mirror, and check the other controls to make sure they work as well.


Take a break, the hard part is done.


Connecting the relay
The relay requires 12v power to operate. Since I wanted to minimize any tapping into the factory wiring of my car for warranty purposes, I chose to use the add-a-fuse kit since it can be easily removed without leaving any damage.


Not every un-used fuse slot has power. In my under-dash fuse box slot 25 was not used, but voltage was available. Since I could use this without tapping any other existing circuit, it made sense to do so. Insert the add-a-fuse into slot 25 in the fuse box, or another slot of your choosing. You won't need more than a 7.5A fuse, I installed two in my add-a-fuse kit since it didn't seem to work with just one installed.


The relay will have a common power source for both the electromagnet and for the switched power itself. Both inputs will connect to the power line from the add-a-fuse (blue and black wires in the kit above) for power. connect the yellow wire on the relay to the yellow wire from the mirror, connect both drivers and passengers mirrors to the yellow wire if you've run both.


Run the other wire from the mirror to a ground, in my case the bolt behind the trunk floor lock.


Before connecting the white wire from the HVAC control, you can test your circuit by connecting it to any ground (including the white wire ground above). Connected directly to ground, it will run so long as the battery has voltage, so only use this for short-term testing. Leaving it for longer would be a bad thing, possibly leading to fire or other damage. You should hear the relay click and be able to feel the mirror warming up.


Connect the white wire from the relay to the tap from the HVAC control panel wiring assembly. This will ensure it only runs when the defrost button is pressed and is automatically turned off once the defroster finishes it's heating cycle or when the car is not running.


Again, this wiring functionally mirrors what is documented in the Honda wiring diagrams, but I can offer no guarantees regarding its safety.


Be sure to tidy up your wiring safely, use split loom tubing and zip ties to make everything clean and out of the way of your feet, brakes, and accelerator. Put the various body panels back on, reversing the process used to take them off. Thoroughly test your car's functions before driving off in it.

 

[bigbossin]

user name - baronvonsmash at ***************
founded this over at the other forum knew it would help

 

[squiggy]

bigbossin Thanks for the detailed info.

So much for the similarity of the different models of the cars. I was hoping that the wiring would be in place with the current harness. At least that would make sense to me from a design perspective that utilizes options for different models. I really don't understand why Honda doesn't make all of the options for the EX-L available for the Si.

I am still curious as to why the parts list for the Si has a heated mirror as a part for purchase, though.

 

[bigbossin]

i got it from another site :/ not my info
yeah maybe because the si is the sporty model and they still want a luxury type civic i guess
for the part list i would say because they do fit

 

[squiggy]

i got it from another site :/ not my info
yeah maybe because the si is the sporty model and they still want a luxury type civic i guess
for the part list i would say because they do fit

Even if it fits, what is the point if it is not an option and it wouldn't be functional?

I would imagine those who buy the Si would want the luxury options. I for one would love heated seats and mirrors. There are many who would like leather. I am still baffled as to Honda not offering power seats for the Civic. However, I am grateful for the intermittent wipers.

 

[bigbossin]

yes very true lol