Getting your own video and audio to route through the VCR connector

[pugwonk]

I was keen to add a backup camera and Android Auto support to my 1998 Century so that I could run Google Maps, Spotify, etc through my phone. Other people have done this by either mounting an extra screen in the car or using a TV modulator to feed a signal into the antenna in the boot/trunk. I wanted to leave the OEM screens and I didn't think that audio quality would be great through a TV modulator, so I instead decided to run my system through the car's built-in VCR connector.

NOTE: My car came with something already fitted that allowed you to watch TV while the car was moving. I don't know anything about it other than that it was attached under the passenger seat and says "TTV145 TV KIT" on it. You'll need this to use the screen while in gear.

ALSO NOTE: This particular setup is only going to work on a car that has a VHS player installed in it. Making it work on a car without a VHS player is going to be a very similar process, but you'll have to work out how it is that the Century detects the presence of the player.

The VCR connects to the car via a wiring harness under the center console. To get to this:

• Pry off the small woodgrain panel that sits between the lower center console and the cubby box. It's a lot less fragile than it looks but you should probably pry it from both sides at the same time. There are three clips holding it on at the left/right/centre.
  
  

  

• Lift the lower center console (around the gear selector). It's held on with clips on either side; I found that the easiest way to get started on this was to pull it directly upwards from inside the cup holder.
  
  

  

  

• Unscrew the two screws that hold the plastic cubby box in there. The cubby box will then lift out - it tips towards the back of the car as it comes out. This will reveal the wiring harness - the lowest connector in this harness is the VCR (not connected in this pic).
  
  

  

I then made a piggback wiring harness that would go between the VCR and the car. To do that you need to buy one of each "colour" of these connectors (the colours just represent male and female): https://www.aliexpress.us/item/2255800566879201.html

The connector is not documented in the service manual so I worked out what I think each pin does using a multimeter and an oscilloscope... bear in mind that any of my assumptions might not actually be correct!

Screenshot 2024-01-22 171726.png (26.13 KiB) Viewed 2851 times

To piggyback the video signal you need to feed composite video down pin 3, left audio down pin 1 and right audio down pin 2. I used 11 for ground but a number of these pins short to ground and I'm honestly not very sure which one the VCR used.

This will enable your own video to be shown on the Century's rear screen whenever you switch to the VCR. If you want to show it on the front screen you can press the third button down on the left to mirror the rear screen. The car remembers this setting even after you switch it off, so you don't have to press it every time you start the car.

To stop other media playing and trigger your video to appear on the screen (as if someone had hit "play" on the VCR) you need to short pins 13 and 14. 13 provides a constant 2.1v signal, and 2.1v on pin 14 triggers the car to stop playing other media and switch to the VCR input.

The VCR is still fully usable once you've done all this, although obviously not at the same time as whatever other video you're putting in there!