I’m going to document my progress on this project here. I found two previous threads on this subject. Both threads are pretty old so I didn’t think I should revive them. Neither thread has any pictures.

Power mirrors on a CRX: How to make it a reality......

Power mirrors for hatchback!

...and this 15 year old thread from another forum with suggestions from someone goes by the name of @Tyson

Power Mirror Alternative

I was inspired to do this after watching this YouTube video. www.youtube.com/watch?v=USU0s1rHhlw

This project will just be adding power adjustable mirrors; they will not be power folding mirrors. I am adding them to a 1990 Civic Si but I think most of the information should apply to any 1988-1991 Hatchback or CRX. I will work on this when I have time but don’t expect me to finish this quickly. If you have advice I would love to hear it. If there is a step that needs more details let me know and I will do my best to add them.

So far I have acquired power mirrors from an EX or LX I don’t think there is a difference but I got them from eBay so I have no way to know exactly what car they came from. I paid $25 for the first one and $35 for the other. I also have a power mirror control switch from Facebook marketplace for $15 which came with the pigtail and another user on Facebook gave me the pigtails for the mirrors, I just had to pay $5 shipping. I also needed the triangular piece of interior trim to replace the one with the hole for the manual adjustment arm. I have seen several options for the interior trim including modifying the trim from a sedan or patching the hole in the original part, but I found a company that makes the trim for a hatchback without the hole and I bought a pair of those for $80. So I have $160 invested in this project so far.

The first step was to remove the glass from the mirror assembly. I would say that the video linked above does a pretty good job describing the process of removing the glass. I would add that after getting one corner free, I found that sticking a piece of tape (I used blue painters tape) to the glass and pulling it sideways rather than prying up on the glass worked quite well and I would say it puts far less stress on that thin piece of glass. I think the key is to take your time and let the butyl rubber under the glass get warm and pliable before doing anything.

I also wired up the mirrors to a 12V power supply just like the guy in the video did to make sure I have working parts. Here is a picture of where I am at so far.

 

We have parallel projects going on For power, you can match the JDM/EDM wiring by taking power from C953 on the fuse box (on the front top right, the two single-plug option ports, it's the left one labelled "1"). It's a 6mm male spade, so you can use just about any female spade terminal. A lot of people use this, but this is the legit one...or just a usual crimp connector. This is fed from fuse 18 (10A). JDM/EDM ground them on G701, which is the ground point holding part of the steering column right behind the ignition switch. It's hard to miss. The black wire already there is the radio ground. Both are convenient for routing power to the switch.

Regarding wiring for the door, sourcing the harness/pigtails from the EX/LX may be the only clean option. I don't particularly want to pay $2-300+ for a main harness on Ebay, then another $100+ on door harnesses just to cannibalize those connectors, so I may end up finding a connector that will work and 3D print a molding to clip it to the door hole. I'm also taking my good ol' time.

I'll look forward to your progress. I should probably take more pictures of mine. Power windows, locks, and mirrors are all in/functional and switches all ready. Just figuring out the method I want to use to pass the wires. And any other wiring to put in place to future proof before puting it all back together...I'd prefer not take it all apart again.

Here's a collection of helpful resources in one place...they're all CRX-specific, but my understanding is the hatch is the same:
Fuse Box Anatomy <-(source)
JDM Wiring Schematic <- (source)
Power Everything <- (source)

 

Thanks for the additional resources. I am planning to run wires before I do anything else, if that turns out to be more work than I want to deal with I might pause the whole project. I was going to run five wires to each door, three for the mirrors and two for the windows. I don't feel a need for a particular connector. Any automotive grade connector that accommodates five or more wires is fine with me. This modification is clearly not OEM so if the connectors inside the door aren't OEM it's not going to bother me, I do agree that if the OEM connectors could be acquired they would be preferable but I'm not sure why I feel that way.

I'm a bit embarrassed to admit that after spending $160 on parts for this, I am having second thoughts about the entire project. (rationalizing) There is a real benefit to the simplicity of the manual mirrors and windows. Also, it turns out that the window switches I was planning to use are not compatible with the OEM window cranks so additional fabrication would be required. My A/C works great so I keep my windows closed most of the time, and I have a spare manual window regulator just in case. I am the only person that ever drives the car so the mirrors never really need to be adjusted. The power windows are really the feature I wanted to add and the mirrors were just an easy "while you are there" project.

If you post your progress, perhaps it will inspire me. I haven't packed it all up in a box yet.

 

That’s all definitely understandable. It’s not a need for me, either…just for fun. I got the car specifically for fun doing projects on it with the goal of staying aesthetically OEM-ish inside, with as close to OEM implementation as possible. Fortunately, I have some spare garage space it can occupy as long as it takes.



If you decide to proceed, the hatch only has speakers for wiring in the door, right? If so, it only has the 2-way connector. So you could just use the readily-available CRX (with door belts) harnesses and you could pass up to 8 wires each side. You could depin your connectors and slide those pins right into the 8-way, and supplement with these terminals:

female: https://www.corsa-technic.com/item.php?item_id=521

male: https://www.corsa-technic.com/item.php?item_id=522

(20-16AWG selection)



Tangent alert: my door connectors will be available soon. I’d like to do my own work on my ICU, but I’d be happy to trade for some ICU work 😁 I’ve been waiting/hoping for when you take it open source…I like to tinker.



Otherwise, I took some photos to show you could potentially feed cables through some gaps in existing door connectors.

8-way door connector:


The fitting around it:


How it fits in door:


Gaps on the sides:


Gaps in the grommet, too (tight):


and just a shot of the male side:


And…. While it’s anlready apart, I decided a couple days ago I’m going to pressure wash my carpet to hopefully adios 34 years of odor. So here’s how it sits, and it really wasn’t that bad to get it to this point:


All the power options in the door (I’ll note aftermarket lock actuators were already there…just weren’t wired up. Tested good, though.)

 

That makes complete sense. I spent several hours puting together some info the other day, but my post said it went for moderator approval. Considering it's still not showing, I'm guessing those hours are down the drain, so I'll limit my future posts.

I'll just suffice to say if you want to pass that many wires, you can do it cleanly with door harness connectors from a door mounted seat belt car (like mine, which will be available at some point). They're 8-way. You would only have to de-pin your current connectors and slide terminals into the replacement connectors. New terminal part numbers are Sumitomo 8240-4422 / Yazaki 7116-1181 for female, and 8230-4282/7114-1171 for male. Corsa-technic is a good source.

 

Looks like your post finally got approved. I have door mounted seat belts as well but I am guessing there are not enough unused positions in the 8 way connectors to add five more wires. Just to be clear, are the 8 way connectors OEM or is that something you 3D printed?

 

Ah. I just learned some more…never realized the HBs came with door mounted belts. You should have the same connector I do, then. The photos are the OEM connector. 6 wires pass thru for seat belts, door latch, and speaker, so that many extras wouldn’t work, unfortunately.