How to: Make your Lilliput lights stay on when headlights are on
Though this has been covered before there is no real How To Tutorial style post that sums it up so that’s what this thread and post is for.
What you need:
- Solder – Get a real thin type of solder because the contacts your going to solder to are very small and close together. you will also need regular sized solder
- Relay – I used one from radio shack SPDT Micromin12VDC part number 275-241 Click Here
- 24-28g Wire – the exact gauge is not that important I think the stuff I used was 26-30g the main thing is that it is small enough to be soldered
to the small contacts
- 20g Wire – This wire is used to activate the coil of the relay and is connected to your headlight switch source
- HeatShrink – Get a size that will work with the wire you chose
- Electrical Tape
- Crimp on Connectors – I used some radio shack ones but your free to use any kind.
- Fine Black Sharpe – to draw the diagram on the back.
Tools:
- Soldering Iron – one with medium heat and a really fine tip is preferable
- Heat Gun – or something that will be used to shrink your heat shrink tubing
- Hot Glue Gun
- Exacto Knife – to scrape away any unintentional connections
- Wire Cutters
- Wire Strippers
Step1: Remove the rear casing and remove button PC Board
Remove the back 4 screws from the Lilliput and expose the back of the screen. Next remove the 4 screws that hold the small button PC Board that the white ribbon cable is attached to. Once you remove the screws the board should come loose. Remove the white ribbon cable by popping the latch up and gently removing the ribbon cable.
Step 2: Solder Leads to the Lilliput button switch pins 12 and 8
Once you have the board free solder the 12 inch long leads of the smaller gauge wire (28g) to pins 8 and 12. The Pin number references are not necessarily the pins from the MFG they are the Pins references on this website
http://www.tmz.com/wrx/lilliputLCD.html.
The soldering is kind of hard because the contacts are very close together. That’s where a nice thin tip soldering iron and very fine solder will come in handy. The easiest way I found to do this was to tin the wire first and then hold the wire on the contact and then heat the wire with the soldering iron. A steady hand is necessary. Use the exacto knife to separate solder from unwanted connectors if you make a mistake.
I used hot glue to strengthen the connections. I used a hole that was already in the case to feed the wires through. Once you get this far you can replace the Lilliput PC Board and replace the cover and 4 screws
Step 3: Wire up the relay
I used a relay from radio shack that was a SPDT Micromin12VDC relay. I mounted the relay on the back of the case with hot glue. I soldered a black and red lead of the larger (20g) gauge wire onto the coil of the relay. The coil, when activated will short out the connection from pin 12 to pin 8 thus turning on the blue LEDS. I then used crimp on connectors on the end of the leads so that I could disconnect the wires if I wanted to remove the Lilliput. Although they were crimp on connectors I soldered them in place to ensure a proper connection becasue radioshack crap is crap.
Then I soldered on the leads coming from the small PC Board on to the relay. Refer to the schematic of the relay and picture. I used heat shrink tubing to cover the contacts and hot glue to give strength so they wont be ripped of by accident (be sure to do this i had to do a repair job shortly after finishing becasue i didn't add hot glue at first).
Step 4:
Tap into your headlight switch
These leads are also going to have the matching female crimp on connectors. Each car is going to be different but the process is the same. To locate your 12v switched headlight wires find something that turns on and off with the headlight switch. Using a multimeter verify. Mine was easy because my HVAC had a separate pair of wires with connector that was tied into headlight switch.
Using the exacto knife scrape away some of the plastic covering of the wires. Get all the way around. Be careful not to dig into the metal at this point. Then attach the your leads and solder. Cover with electrical tape. Crimp the matching crimp on connectors onto the ends. Connect to the matching wires on the relay (coil) Polarity doesn’t matter here just as long as they connect to the pins that go to the coil. See diagram above
Final Thoughts:
Once you connect everything if you wired it up properly your blue lights should come on and stay on when you turn on headlights. Also your buttons should work like normal.
Enjoy
Linear Mode
