Clock fix and upgrade - tutorial

The clock in my 2000 Tacoma stopped working. Call me old-fashioned, but I need my clock I know I can get one on eBay, but I like to fix things on my own if possible, and I thought it might be a fun project. I had a few prerequisites:

• As cheap as possible
  
  
• No permanent modifications to the truck
  
  
• Use the original clock enclosure and the original plug

Since I'm already working on it, there's another annoying issue to address: you have to set the time manually after the battery is disconnected or when you change time zones on a road trip.

So, here is the project: a self-setting Tacoma clock. There are a few ways to get the current time, but the cheapest and easiest is GPS. And since I'll already be reading GPS, I might as well grab the current location to know where I am when traveling. Here is a sneak peak at the final result:



Disclaimer: This was an impulsive idea, no research has been done, etc. I just thought I wanted to do it, bought the cheapest parts I could find without putting much thought into it. So there may be better/more efficient ways of doing it, but this is what I did and I'm just sharing it.

Parts list and prices:

• Microcontroller: I chose Raspberry Pi Pico, but Arduino or anything else will work too - $4
  
  
• Display: I chose the cheapest I could find, which turned out to be a bit too small but it works - 0.96 in SSD1306 128x64 OLED display - $1.70
  
  
• 12V to 5V buck converter - $0.60
  
  
• GPS module: again, I chose the cheapest I could find and it's actually pretty good - NEO-6M - $2.80
  
  
• Thin wires to connect everything: I used wires from inside an Ethernet cable - $0.20

The total is around $10. You will also need a soldering iron to connect everything. You could probably also do all of this using jumper wires without soldering, but it would be messier.

Here is the summary of the idea: grab the 12-14V from the battery that comes to the clock plug, drop it down to 5V to power the Pico, use the Pico to grab GPS data (coordinates and time), display the time, and use the coordinates to display location (closest town).


Step-by-step instructions:

• Remove the clock and bring it home.
  
  
• Disassemble the clock (4 tabs to pry on the sides of the enclosure).
  
  
• Remove the clock circuitry (two PH1 screws). Keep the screws.

1. Putting your new clock together
   • Below is the diagram of how I connected everything. I soldered everything straight to the Pico and the peripherals. I wanted to install it and never take it out again, so I made it permanent. The power to the voltage regulator will come from the plug. The smallest automotive flat connectors (2.8mm) will fit well.

• Upload the code to your Pico. I'm attaching the code I used at the bottom of this post. I'm not a programmer, so it’s probably not optimal, but it works for me. I even designed my own fonts for displaying the time. The biggest caveat is that there is not much space on the Pico for keeping geographical data. So I only included towns that are within a 200-mile radius from my home. You will have to swap the list of cities to your own, unless you live in southcentral Wisconsin. If someone knows how to conveniently store and access large lists in a Pico, please let me know. This will still work if you go outside of the 200-mile range; it will just stop displaying the name of the nearest town and will start displaying "Toyota Tacoma" instead.
  
  
• Connect the female flat automotive connectors from your automotive regulator to E(-) and ACC(+). The markings are on the back of the enclosure. ACC(+) will make it work only when the key is turned, but you can make it work 24/7 if you connect to B(+). It draws around 32 mA of current, so you technically could do that, but I did not see the need to have it on 24/7.
  
• Shove everything into the enclosure. The only thing that actually has to be secured is the screen, which I positioned to fit the clock "window" on the enclosure and secured with double-sided tape in the corners. You can secure other stuff if you want - I reused the screw and screw post and screwed down the Pico, the rest I just tucked in loosely. The square antenna did not fit inside, so I put it on the outside - I bent a small protruding piece of the enclosure a little so that the wire can pass, and I put the antenna on the back of the enclosure with double-sided tape.
  

At this point, you can "bench test" your device. Plug it into either 12V through the voltage regulator or just power it by USB to the Pico. Put it on a windowsill or outside so the GPS can grab the satellites. With the small default antenna, it may have trouble finding a signal through walls.



You are done You can put everything back into the truck. Plug it in as if nothing ever happened, and that's it.

The GPS needs some time to acquire a signal. So after you start the truck, you will see a time of "8:88", text saying "Toyota TACOMA", and a Toyota logo. In half a minute or so, it should get the GPS signal which will give you the current time and location. For my purposes, I used the remainder of the screen to display two other times: the time back home in case I drive to a different time zone and the time in Europe. I also display the coordinates in a tiny font. I'm not sure what for; it's probably not useful, but I paid for the whole screen, so I will use the whole screen But you can display whatever you want there. The code is extremely simple. And you need to change the lists of cities and coordinates to your location if you are using a small controller like the Pico because it can only fit a limited amount of data.





The obvious bad choice I made was the small screen. If I were to do this again, I would have gotten a bigger screen. Pretty much the whole clock above the buttons is transparent so it could accommodate a much bigger display. It would be very easy to do, just need a bigger screen and some trivial adjustments to the code. But it is what it is, I'm happy with it, and maybe some of you can benefit too.

I hope this is useful to someone or will inspire similar projects! And please let me know if anything is not clear in my post and I'll try to edit. Thanks!

 

That is fucking sweet

 

^^^^ What he said.

 

I love Tacomaworld

 

Those burn marks you pointed out are normal, it is called a getter. The VFD (vacuum florescent display) screen is a sealed vacuum, but it is possible that the materials in that vacuum absorbed reactive elements like oxygen before it was made, and those elements could be released later and break the display. So the getter is sealed inside to absorb these potentially damaging gases.

Those burn marks are the getter, and if it were white that would indicate the screen was broken. If it's black like that it's actually a good thing because it means the getter isn't used up. I'd bet the actual issue was a broken solder joint. My 4runner clock looked the same way, but it worked after I fixed up the joints.

 

Nice, right up my alley, been doing a lot with Arduino.

Have you figured out how to see it without moving out of line of sight of the steering wheel?

That's my only real complaint with the first gen, the location of the stupid clock!

 

X3!
That's friggin badass!

 

Gotta remember this thread for the future "I think there is a gps tracker in the truck I just bought" thread.

 

This is a great point, and thanks for the nice explanation! It did not even cross my mind that this may be an old school vacuum device. After reading your comment I did try to see if I can make it work, but could not. I'm not throwing it away, and the mod is fully reversible so I may give it another shot one day, but honestly I like my mod maybe a little more than the original clock I edited my post and removed my claim that the burn marks were the issue so it does not confuse anyone. Thanks!

Yeah, that I did not solve It is squeezed to the right, which is the most visible place in that clock window, but still the wipers stalk and steering wheel block it a bit not my fault though!

The gps is entirely local, it only grabs information form the satellites but is unable to send it out. I actually thought of this, being able to track my truck would be great in case someone steals it, but this requires constant internet/phone connection to send the tracking information, which costs money and would require additional work so I decided not to.

 

I can't say I blame you, I thought the exact thing when I opened mine. Normally when you see these screens their terquoise like my alarm clock, Toyota put a filter over it to make it orange. Posey on youtube made an amazing video on them that showed the grid, and the texture of the phosphor print as it fluoresced.

Anyway, it is more functional, and it matches pretty much spot on. I did a similar thing when I was looking for an outside thermometer to put in a switch blank. The screen looks a little off center in your photos. If I had a Pico I'd fidget with the font to make the time mimic the original 7 segment display even if it's slightly less legible

 

Definitely going to do this!

 

Great idea and write up. On my to do list now--thank you!

 

Cool! Rediculously overkill for a pico but they're so cheap anyway Bonus points for including the code. Someone should try to get the factory buttons working

 

Great job, sub'd, I will do this someday.

 

Wonder how to do something similar for the 2nd gen clock…

 

there are some really crafty people here on TW. What a really cool "Handmade" Clock. Fabricators of metal, clocks, Stereo installations, and just about any repair you could possibly think of is also available here on TW. Your Score for the Clock is

 

Very freaking cool, hermano

 

the 2gen tacomas make it hard to do this mod. Because the clock is integrated into the center stack with the hazards and airbag light. It is all one piece.

 

@emilphysics so when are these going up for sale? I'd be sweet if you could add ambient temp to it. I bet most people would pay 50 to 100 easy. The only other way to get something comparable is a rear view mirror swap for 300.

 

It's literally free with instructions dude lol

... OK, 10 dollas