Compass rearview install instructions

[KDirk]

After some tribulation, I have installed and tested the compass/map light rear view mirror from the 1992 Roadmaster in a Reatta. Following are instructions for wiring the mirror to a Reatta.

Referring to the attached diagram, the compass rear view mirror has a 4 pin connector with the following wires [note the letter is the cavity ID stamped on the connector shell]:

A: black/white stripe; courtesy light ground (unused on Reatta)
B: black/no stripe ; main ground (must be connected)
C: black/green stripe; +12VDC for map lights
D: black/blue stripe ; +12VDC for compass

Now, the Reatta has a three pin connector with only two wires:

A: brown/white strip ; +12VDC (hot in accessory & run only)
B: black/no stripe ; ground
C: no connection

So, the following connections need to be made:

1. Black/no stripe wire on vehicle side harness to black/no stripe wire on rear view mirror harness.

2. Brown/white stripe wire on vehicle side harness to black/blue stripe AND black/green stripe on rear view mirror harness. Note that both these wires (black/green and black/blue) must be tied to the brown/white 12 volt supply for both the compass and map lights to operate.

The black/white stripe wire can remain unconnected as it is unused on the Reatta. Note that when grounded, it turns on both map lights in the rear view mirror, overriding the internal map light switches. This is for applications where the map lights double as courtesy lamps.

As far as mounting, the mirror mount is the same as the Reatta stock mirror. A single torx screw holds the mirror mount to the retainer on the windshield.

Once all the wiring is connected and tidied up, turning on the ignition to accessory or run should cause the compass display to light up with a pale blue background. The current direction should appear shortly.

I have noted that if there is a long delay before the direction appears, the mirror needs calibration. The calibration instructions follow:

1. Drive to an open level area and park vehicle. Maintain distance of at least 20 feet from other vehicles and 100 feet from buildings and other metal objects.

2. With the engine running, push and hold the push button located on the drivers side of the rearview mirror bracket. [This is a small black flush mounted unlabeled button about 1/4" diameter in the lower extension of the mirror mount base]
The display will go blank. In about three seconds, the letters "CAL" will appear in the display. Continue to hold the button until a symbol resembling a number "8" appears then release the button. The display will begin to blink.

3. After one or two minutes, the display will change to show two symbols resembling the number "88". Now turn the vehicle in the opposite direction (180 degrees), within two minutes.

4. Push the button until the display begins to blink, then release.

5. After another minute or two, the display will change to a slowly blinking "N".

6. Now point the vehicle North, you will have two minutes to complete this step.

7. Push the button a final time, until the display stops blinking and "CAL" disappears. The compass is now set.

A couple of final notes:

The vehicle side harness in the Reatta is tucked up above the headliner. When pulled out, there is very little (about 2-3" worth) wire to work with. This makes the connections difficult, so be careful to cut the connector off as close to the shell as possible.

I managed to re-pin the harness on the rear view mirror re-using the 3 pin connector shell on the stock mirror to avoid cutting off the vehicle side connector in the car, but this is a very nasty job on this particular connector type. Chopping the vehicle side connector is probably easier, although I understand some may not like that approach.

Since the compass and map lights are both powered from the same 12 volt switched supply, the compass will operate in retained accessory power, just as the map lights will.

If there are any questions, or clarification needed, please PM me.

KDirk

[nic walker]

Very Nice Tutorial Kevin.... [img]<>/smile.gif[/img] Thanks

[DAVES89]

Kevin,
I printed off your instructions. Thank you very much for your efforts. There are still about 4 Roadmaster mirrors if anyone is interested. While I am out there I will also stop at a Riv and cut off the car side of the mirror harness. I can then wire it up on my bench and quickly install it in my Reatta.
Lets see I did the Riv compass upgrade to my Crt, I have a GPS and now this...
Maybe a sign I need some direction in my life? [img]<>/confused.gif[/img]

[dpannell]

Dave, Would love to see pictures of the GPS installation in your 89'. The Garmin I put in my 90 has performed flawlessly and most people are surprised when I flip it open. Dave

[handmedownreatta]

is there a auto dimming/compass mirror available?

[KDirk]

Gentex does make an auto-dimming rearview with compass and map lights, but it is not so easy to find. It is also expensive, about $250 last time I saw one in a catalog. Also has LED map lights, not incandescent if this makes any difference to you.

I believe JC Whitney sells it, and there was one other place [name escapes mt right now] I saw it sold on a website.

This approach would require additional wiring, and these mirrors may also be near impossible to install on a Reatta without modification due to the location of the mirror retainer on the windshield.

The newer style auto dimming compass mirrors have a slide over clip mount, not a set screw. Also, the mirror mount has a "box" built onto it that houses some of the electronics. Look at any newer GM car with a compass/onstar mirror to see this. Do not confuse this with the rainsense auto wiper sensor usually mounted just to the right of the rearview mirror.

Because the retainer on the Reatta is glued to the windshield less than 1/2" below the headliner, sliding the mirror mount up and over the retainer and getting it to clip on would be very difficult due to lack of headroom.

Of course, the retainer could be removed and glued back on lower on the windshield, but that just makes more work. That, and the cost, deterred me from buying one of the newer Gentex mirrors and installing it in my car.

The mirrors Dave found are a good compromise, as they have the compass and map lights and look almost identical to the stock Reatta mirror in size and shape. They also have the set screw mount which is much easier to deal with.

Best of all, if you can find them in a salvage yard they are bound to be relatively cheap. Do be forewarned, the back light on the compass display may be burned out as it is a 12 volt micro lamp and these mirrors are all 16+ years old now.

I repaired the bad backlights on both units Dave sent me with white LED's which worked out very well, and will not burn out again (well, not for 100,000+ hours anyway).

If there is sufficient demand for this mod, I will work up instructions on how to replace the bulb with an LED. Not terribly difficult, but getting the mirror apart without damaging anything is tricky. The LED also requires a dropping resistor to bring the lamp voltage down from 12VDC to about 2.5 volts. Some soldering and heat shrink tubing is also required.

I will add some pics later today of the new mirror installed in my car.

KDirk

[DAVES89]

There is not an auto dimming compass mirror in any of the G M cars I looked at in the u-pick yard.
If anyone is interested I have one Riv mirror that is excellant [very similar to the reatta, wiring connection is different. I would just use snap locks]and one compass mirror [there are no more out in the yard at this time]available. I was going to install the Riv mirror in my Reatta, but will be installing a compass mirror instead.
PM me if interested.

[Reattatude]

BTTP for those mirror pics, Kevin ; )

[KDirk]

Reattatude,

Yeah, my bad. I took the pictures but was not pleased with the way they looked. I did it during the day, but I need to get out at dusk to get a good pic of the mirror in use. Problem is that the sunlight coming through the windshield washes it out and all I get is a silhouette of a rear view mirror, and the compass is not even visible. Other option is to get to a nearby parking garage.

Will try to get new pics taken tomorrow and post shortly thereafter. Would've done it sooner but I've been getting killed with overtime this week. Not that I'm complaining, with so many people just scraping by these days...but it is cutting heavily into my Reatta time.

KDirk

[DAVES89]

63viking installed his. Maybe he can provid pictures...

[Old Guy]

This is the best I could do.

[Old Guy]

Sorry wrong post.

[63viking]

Pictures of rearview mirror.

[KDirk]

Jon,

Thanks for getting the pictures up, yours turned out far better than my first attempt. Out of curiosity, did you cut off the vehicle side harness connector to wire yours in? I ask because I used the factory harness, and re-pinned the mirror harness using the stock Reatta mirror 3 pin connector shell.

This saved my vehicle side harness, but it is a very tight fit as there is essentially no slack at all due to the short length of the harness on the compass mirror. Also, the connector now sits just below the edge of the headliner, not tucked above it as it was with the stock mirror.

I'm thinking I may redo it to eliminate the above issues, and would like to know how you did yours.

KDirk

[handmedownreatta]

thats cool....

[63viking]

You asked about how I installed my compass mirror.
I soldered two pieces of sanded paper clip, to the compass mirror wires. About 1/2 inches long, with heat shrink tubing over them. This left about 1/4 inch sticking out of the shrink tubing. I plugged those into the plug from under the headliner and pushed it all back under the headliner.

[KDirk]

Jon,

Thanks. Simple, but it works. I think I will rework mine due to the shortness of the harness causing the connector having to be exposed outside the headliner.

KDirk

[63viking]

I was able to tuck the connector and the wires back up under the headliner.

[imported_Dales90]

Guys,
Auto-dimming, map-lighted,compass rearviews in late Rivs. both my 95 and 99 have them

[wws944]

Bought a compass/map light mirror from a '92 Roadmaster at the Pick N Pull. Since it has the square 2x2 pin connector, and the Reatta mirror has a flat 1x3 pin connector, I made a little adapter cable for a plug 'n play installation. Flat 3-pin plug came from a early-90s Cadillac - where they used their own little adapter cable between the back of the mirror and the cars wiring harness.

Ronnie: You might want to add to your compass mirror instructions that, at least on the convertible, the trim cover needs to be removed to access the wiring. To do this:

1.) Unscrew the visor clips - one Phillips screw on each. Note that on the convertible, the clips stay with the trim piece, because there is a second screw on the back of the trim piece holding them on.

2.) Unscrew each of the visors - three Phillips screws on each. Gently let them drop and hang by the wire.

3.) Unscrew the black Phillips screws - one at each end of the trim piece. On the convertible, the ridge around the black top plate may get in the way of the screw. If so, loosen the end screw on the top plate a bit in order to be able to lift the plate slightly to get the needed clearance.

4.) To remove the mirror, use your trusty T-15 torx driver on the set screw holding the mirror to the button, then lift it up and off.

Convertible owners may also want to take advantage of the opportunity to replace their broken original visor clips with Kingsley versions while the trim is off.

Reverse the above for re-installation of the trim.

[Ronnie]

I have updated the tutorial to include the instructions for removing the trim. If corrections are needed let me know.

Did you find the original instructions helpful when you installed your mirror?

[wws944]

Looks good - though you might want to add the bit about building an adapter cable. I am not a fan of cutting up factory wiring connectors.

Really helpful is the calibration instructions. They seem to be found no where else on the web. The Donnelly mirror is different than a Gentex mirror, where the latter simply needs to have the correct zone set.

[DAVES89]

I just used scotch loks on my connections, then tucked it all in...

[wws944]

Ronnie: I was looking at the coupes yesterday at the Reatta Rally, and my instructions above for removing the trim cover are indeed convertible specific. For the coupes, I guess you would simply unscrew the visor clip screw on each side, maybe the visors themselves, then gently work the center of the headliner edge down a tad so that the connector can be slid out.

In the coupe, do the visor clips have a second screw from above to hold it to the headliner? Or is there just the single screw going upwards?

[NCReatta]

Just a single screw on coupes.

Due to the flexibility of the headliner board, you should be able to pull the plug out without removing the clips.