Software engineer Jeff Lau, posting under the username UselessPickles, showed off the restored car phone in a video uploaded to YouTube. The Mitsubishi came from the factory with an optional “DiamondTel” handset and hands-free system, which was rendered inoperable by the discontinuation of analog “AMPS” cell service in the U.S. in 2008. (The 3G shutdown bricked a ton of newer cars’ connectivity features, too.)
After three years of work, Lau restored the device’s functionality using a custom Bluetooth adapter. Lau engineered the adapter to piggyback between the stock phone transceiver and hands-free control unit located under the trunk carpet. That let Lau tap into modern cell networks with his 1993 car phone—but he didn’t stop there.
Paired with a smartphone, the stock handset displays the name of the paired device and the signal strength of the smartphone’s network. It gets better: The car’s hands-free microphone feeds the smartphone voice commands (to Apple’s Siri in this case). It’s pretty much all the functionality of a 2023 hands-free system but without the distraction of a touchscreen.
Obviously, that isn’t about to become a widespread resto-mod trend soon. The lengthy dev time, low take rate of car phones in their day, and uniqueness of individual cars’ systems mean we’re probably not about to see off-the-shelf car phone restoration kits soon. But the fact that bringing car phones back is possible will hopefully inspire someone else out there to resuscitate theirs—maybe even one of those retro Chrysler VisorPhones will ride one day again. Or ring, I should say.
The whole process is laid out in this forum thread, starting on 23/12/21: Making a Bluetooth adapter for a Car Phone from the 90’s