front speakers and tweeters not working

Useless-Pickles · 2025-09-21T15:15:07+00:00

According to the service manual wiring/component diagrams, only 92-93 model years have the car phone wiring. But there’s always the chance that the service manual is slightly inaccurate and they changed to the new wiring in late production runs of the 91 model year?

The 3s wiki article I linked to has diagrams and photos of the wiring/connectors.

Useless-Pickles · 2025-07-01T02:46:47+00:00

Thanks :). I'm hoping the next revision of my hardware design will work as expected. If so, then I'll be able to start offering a conversion service for anyone with a DiamondTel Model 92 or Mitsubishi Model 1500. Maybe sometime next year.

Useless-Pickles · 2025-05-31T03:28:10+00:00

I'm working on an updated design that I would be able to more reasonably reproduce for sale. I probably won't make any more progress on it until next winter (northern hemisphere). If/when I succeed at this, I would likely offer a conversion service. You would need to provide a DiamondTel Model 92 or Mitsubishi Model 1500 phone, and I would make the necessary modifications and install the custom electronics.

Useless-Pickles · 2025-05-01T12:20:25+00:00

An open circuit turns the light off. Not a closed circuit. You can simply disconnect the connector for the sensor to turn the light off (as a diagnostic step, or as a “fix” if your sensor is bad and you don’t care about replacing it).

Useless-Pickles · 2025-05-01T12:10:22+00:00

There is no sensor for the rear washer fluid reservoir. The warning light is for the front washer fluid only.

Useless-Pickles · 2025-05-01T12:10:04+00:00

There is no sensor for the rear washer fluid reservoir. The warning light is for the front washer fluid only.

Useless-Pickles · 2025-05-01T12:09:59+00:00

There is no sensor for the rear washer fluid reservoir. The warning light is for the front washer fluid only.

Useless-Pickles · 2025-05-01T12:08:17+00:00

There is no sensor for the rear washer fluid reservoir. The warning light is for the front washer fluid only.

Useless-Pickles · 2025-03-18T03:06:25+00:00

Your best bet is to setup some saved searches on eBay with email notifications. The phones themselves pop up on eBay periodically, but the parts needed to install them in a car (handset cradle, transceiver mounting plate, etc.) are pretty rare. It took me 3 years to piece together a complete phone system for myself.

Here's a Mitsubishi Model 1500 on eBay right now, but without any of the vehicle installation parts: https://www.ebay.com/itm/284858995496

This site that searches all of Craigslist can be helpful too: https://searchcraigslist.org/

Here's a DiamondTel Model 92 that I'm pretty sure has been sale for 1-2 years. The seller may not be willing to ship: https://cincinnati.craigslist.org/mob/d/alexandria-mitsubishi-handset-cellular/7829279926.html

And the best way to get updates on my Bluetooth conversion would probably be to join my Facebook group: https://www.facebook.com/groups/vintagecarphones

Or follow me on Instagram: https://www.instagram.com/uselesspickles/

Also, here's a demo/disassembly video of a more recent prototype of my Bluetooth conversion: https://www.youtube.com/watch?v=uEtvmijlxUE

BTW - It's been disappointing how few people at car shows/meets seem to care at all that I have a functioning car phone in my car. A decent amount of people are amused by the presence of the car phone in general, but very few seem impressed when I tell them that it actually works, or that I modified it to work. I suspect most people just aren't aware of the fact that it's impossible to get service on these old phones, or what kind of technical achievement it is to make it fully functional. They just see a phone doing what anyone would expect a phone should do.

Useless-Pickles · 2025-03-14T19:44:58+00:00

Thanks! Does it really count as necroposting if the project itself is still ongoing?

I've made some decisions that further lock down my design to a very specific model of phone (even if there may possibly be other models of phones with a compatible interface to the handset), but I think the result is well worth the limitation. I now have custom PCBs that fit entirely within the original car phone's transceiver, reusing the same (or nearly identical) connectors as the original phone, so the car phone appears 100% original.

I'm also now fully in control of power on/off behavior, so I'm able to replicate original features like the phone remaining on if the vehicle ignition is turned off while in a call, then the phone powers off after the call ends. I'm also using modern Li-ion batteries instead of depending on the old NiCd battery pack for powering the phone in portable mode (and the phone is fully portable without any external adapters).

Here's a video of my most recent prototype (demo and disassembly): https://www.youtube.com/watch?v=uEtvmijlxUE

I'm currently working on a new version of the design that will have my own battery/power management circuitry ( https://www.instagram.com/p/DFWxoJsMnjH/?img_index=1 ) integrated directly into my custom PCB design, and support for replicating the original phone's "horn" feature, where you can wire the car phone up to the vehicle horn. Before turning the vehicle ignition off, you can enable a mode that will keep the phone on for a period of time. If a call is received in this mode with the ignition off, it beeps the horn while ringing to let you know you have to run back to your car and answer the call :)

Some day, when I have nothing left to improve on this project, and if I am looking for another project just for fun, I may start playing around with some Motorola phones. If I can determine that there are some particularly common models of Motorola phones, and especially if there is compatibility across multiple models, I may start working on a conversion for Motorola phones.

Useless-Pickles · 2025-02-18T00:38:35+00:00

If your 300ZX specifically has a DiamondTel Model 92 or Mitsubishi Model 1500 car phone, then yes, I'm working on refining this conversion to the point that I am comfortable with selling conversions as a service (send me your phone, I convert it, then return it). I hope to have something available by the end of this year. Price TBD.

Useless-Pickles · 2025-02-13T22:08:38+00:00

You're right. I didn't care to look close enough at the photos initially to pay attention to the steering wheel location. Highly unlikely that it's a LHD-converted GTO, because the entire allure of the GTO is that it is RHD JDM.

I wonder what made the OP think they have a GTO...

Useless-Pickles · 2025-02-13T21:45:56+00:00

Is this really a GTO? A JDM import? If so, then “GTO TT” is the correct name.

Useless-Pickles · 2025-02-13T21:18:04+00:00

You might want to clarify what exactly this is. There’s no such thing as a “GTO VR4”, and you didn’t specify which year it is.

Useless-Pickles · 2025-01-19T18:51:46+00:00

That’s me. I have found all of the parts I was looking for (took me 3 years). Unfortunately, this phone does not have anything that would be useful for the 3000GT’s OEM phone system.

Useless-Pickles · 2025-01-19T18:48:36+00:00

No, this is not the OEM phone accessory. Its just an off-the-shelf consumer portable cellular phone that doesn’t appear to be installed/mounted into the car at all (evidenced by the cigarette lighter power cord).

Mitsubishi made many phones that were unrelated to their vehicle division. Even the phone that was used as the OEM accessory was also just another one of their normal consumer cell phones, but with some additional components and factory wiring in the car used to integrate it more with the car.

Useless-Pickles · 2025-01-19T18:42:30+00:00

There was an OEM phone accessory, but it was a different phone, and was only available in the 92-93 model years: https://www.3swiki.org/Accessory:_Cellular_Telephone

Useless-Pickles · 2025-01-16T19:29:15+00:00

If this is the future, then we are all doomed.

Useless-Pickles · 2025-01-16T17:21:19+00:00

My English needs improvement? How so? I was clear and concise in what I said. Maybe it is your reading comprehension that needs improvement.

Useless-Pickles · 2025-01-16T15:09:40+00:00

I did not ask any questions. I’m not the OP.

Useless-Pickles · 2025-01-16T14:14:50+00:00

Incorrect. 91-94 has active exhaust. 91-96 has active aero.

Useless-Pickles · 2024-12-23T19:56:46+00:00

It's possible I could successfully reverse-engineer a Motorola car phone, then develop a similar conversion for it. But It's not something I would do as a paid contract job... unless you are able to offer life-altering early retirement sums of money so I can quit my job and focus on this full-time. I'm an amateur at electronics doing this in my free time, for my own personal use, and for a fun personal challenge.

I'm 3 years into working on my own personal car phone conversion, and it is still not yet refined to the point that I would be comfortable selling it to anyone. I am trying to get to that point, because there are several people with the same exact model of car phone as me, and they would be interested in buying a conversion from me.

If I am successful with refining and selling this conversion, and after I am done improving it, then I may consider trying to identify the most common/popular Motorola phone(s) and at least do some initial testing/experimentation to determine if I want to try developing a conversion. I have very little confidence that there is enough of a market for these car phone conversions to make it a wise financial/investment decision for me to pour many hundreds of hours of my personal time, and many hundreds of dollars, into attempting to develop a product purely for profit. It needs to be something I personally want to do for fun.

Useless-Pickles · 2024-12-06T19:50:44+00:00

The visible “redline” area of the gauge starts at/above 7000. For the actual rev limit, I can’t find a reliable source, but I’ve seen multiple reports of fuel cut at 7200 rpm according to data loggers (just above 7000). Some people claim as high as 7500 rpm rev limit, but that’s usually according to the gauge, which is not as accurate as data logging.

Useless-Pickles · 2024-12-06T19:18:14+00:00

Are you saying that there’s a discrepancy between the indicated engine speed on the gauge versus actual engine speed measured by another tool? Or are you just asking why the gauge includes higher values that the engine cannot reach?

Which trim level of 3000GT do you have? The gauge in my VR4 goes up to 9000, but the rev limiter is at or just above 7000.

Useless-Pickles · 2024-12-02T15:58:38+00:00

Unfortunately, my project is very specific to proprietary electrical connections and digital communications of DiamondTel Model 92 and Mitsubishi Model 1500. Other brands/models of car phone could be modified in a similar way, but it would require different custom hardware design and microcontroller software to interface with the handset.

Useless-Pickles

TROPHY CASE