Factory Cellular Telephone Accessory (DiamondTel Model 92)

It’s not common knowledge, but there was an official cellular telephone accessory available in 1992-1993 3000GT/Stealth (at least in the US; that’s the most I’ve been able to 100% confirm). The car is pre-wired from the factory for a plug-n-play dealer install, with integrated hands-free operation (controls on steering column, radio auto-mutes and phone audio goes to front passenger-side speakers when in a call, etc.).

I’ve been researching this accessory and gathering parts for nearly a year to install it in my 93 VR4. I have now started consolidating everything I have learned about this phone system on 3SWiki: Accessory: Cellular Telephone

Check out the 3SWiki page and let me know if:

  • You have any questions.
  • You have this phone system or any parts of it that you would sell (I’m still looking for a couple parts).
  • You have any additional info/details about the phone system that I haven’t documented yet.
  • You have details about variations of this accessory in other markets around the world (was it available?, did it use a different model of phone?).

Here’s a few pictures of the phone in my car (NOTE: the official location of the handset is under the arm rest, but I have not found the proper mounting bracket yet, so I used an aftermarket mount on the side of the center console):


This is so crazy cool and 90´s … I like it alot, just for the show factor it gives

Exactly :slight_smile:. This car is already so full of crazy cool 90’s technology and styling, but more is better. As soon as I learned about the cell phone accessory from an original sales brochure, I immediately wanted it. I don’t like having unused potential in a car like this. There’s 5 “spare” connectors among the factory wiring harnesses that are destined to plug into phone components. Destiny must prevail!

It’s slightly more than just “show” factor, because the phone does power on, and you can dial numbers (with accompanying nostalgic dialing sounds), mess around with the phone’s settings, create entries in phone’s contact list (names + phone numbers), etc.

The button pad and display are also backlit for additional cool effect at night:

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I have that in my 92 VR4, but I never new what it was. Lol. I thought it was something the first owner put in. It doesn’t have the phone but everything else is in the trunk.

Nice! Please check your messages :slight_smile:

Check out this sales brochure I found for the phone.

PDF scan (high quality): https://www.uselesspickles.com/files/3000gt/DiamondTel%20Model%2092%20Brochure.pdf

Preview images (lower resolution; small wording hard to read):


I’ve got the wiring in the car for this but no other parts. I do however have a Wonderful Spectrum radar detector that’s still functional.

My 91 had this as well. I’ve removed it and have it in stage at the moment.

@91GTOtt Only 92-93 model years were wired from the factory for the official accessory install with hands-free integration, so your 91 most likely had an aftermarket install of a phone. There’s a chance that there could be a difference in the GTO vs 3000GT/Stealth in terms of which years supported this. If you have any pictures of the parts, I can help confirm/deny this.

If you actually do have the parts for the official accessory installation, I’d be interested in buying them.

I’ll have to dig it out of storage and take a picture for you to check it out. It’s only the hardware that’s mounted in the back of the car.

Bump for visibility. I’m still looking for some of these parts.

@Diazjunito76 - would you sell me what you have? Please send me some pictures.

I found a 93 VR4 for sale on Cars.com that has the phone installed. It is a green one owner car. Unfortunately, you can’t see a lot of detail. It can also be seen at garagekeptmotors.com.

Thanks for the heads up, but that’s not the OEM car phone. Just an aftermarket Panasonic phone install that wouldn’t have any of the parts I’m looking for.

BTW - I now have the proper OEM mounting hardware for the handset:

Now the last part I still need is the “HANDS-FREE CONTROLLER UNIT”:

Bump! I’m still looking for parts.

@91GTOtt @Diazjunito76 I’m still interested in the car phone parts you have. Please let me know if you are willing to sell and send me pics of what you have.

Bump again!

@91GTOtt and @Diazjunito76, please check your private messages and respond.

I haven’t found where it is. I’ll be moving my storage unit a couple months, I’ll keep an eye out for it.

Thanks for the update. I’ll keep my fingers crossed.

If Mr. Pickles finds his parts I need the handset free module in the trunk as well. My 1991 had it as dealer installed but not with the column push button assembly nor the glovebox mounting. If Mr. Pickles gets his parts I need these as well. Thanks!-Kip 913-710-4155 [email protected] Kristopher Kip Wendler on FB. All of you hit me up with a friends request.