VTEC Engine Light Mk.2

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VTEC Light Mk.2 by JayJay

Part 1: What you'll need

Well, first of all you'll need:

  • 1 x set of EL Dials
  • 10 x 10 Ohm resistors (Maplin Code M10R)
  • 1 x Relay (Maplin Code N08AW)
  • 30 x Super Bright LED's in a colour of your choice, I used red (Maplin Code N22BY)
  • 1 x Fuse Holder (Maplin Code KU30H)
  • 1 x 5 Amp fuse (Maplin Code AR38R for a packet of them)
  • 1 x Soldering Iron
  • 1 x Electrical Solder
  • 6 x Spade Terminals (Male and Female, might as well get a packet of 10 to be safe)
  • 1 x wire (Maplin Code BL94C)
  • 1 x 6ft wire (from any hardware store)
  • 1 x voltmeter
  • Glue (I used Araldite 2 part glue)
  • Drill and drillbit with diameter slightly smaller than the LED's
  • Various sized screwdrivers
  • Rachet with various sized bits and extender (for removing the ECU if need be)
  • A lamp (for when working in the footwells)
  • Lots of patience!

One note about the wire, I used the above wire (Maplin Code BL94C) for the wiring in the EL dials as its thin and easy to shape. Outside the dials, as I had run out of said wire, I got a 6ft roll of 5 Amp wire. This was just the right amount, with a little bit extra for a bit of leeway. I recommend doing this as the thin wire is perfectly for the use in the dials as it keeps its shape, but outside once its being run around the engine bay/interior the flexible wire is much easier to work with! I found that the tip of the thin Maplin wire kept snapping off once the plastic was stripped as well.

In regards to the spade terminals, four of them are for the relay. However, when making mine I didn't have enough so I soldered the VTEC signal wire and Ground wires onto the relay, and used the spade terminals for the battery and LED +ve connections. Unless you're amazing at soldering I'd recommend using the spade terminals for at least the VTEC signal and Ground connections as it is a very tight spot.

Always buy a few more than needed (i.e. 30 LED's when 25 are needed) to cover accidents, breakages, changes in the plan etc! For example I was originally going to use 30 LED's, but there isn't enough space, and to keep the 10 Ohm resistors it had to be changed to 25 LED's. So, if you use less LED's you have to change the resistors values.

Make sure you cut into the right wire on the ECU! The VTEC signal wire is green with a yellow tracer. There is another wire that is yellow with a green tracer! The wire you cut in to is green with a very thin yellow stripe. I'm not sure if the colour is different between UKDM and JDM ECU's either, mine is a JDM and the VTEC signal wire is green w/ yellow tracer. Make sure of this.

Also, disconnect the battery positive connection before proceeding with Part 6.

Part 2: The wiring diagrams

The base idea:


The resistor setup:


Relay Wiring:


As VTEC comes in a relay will switch on, powering an LED array within the dials, changing their colour. The relay will switch when receiving a signal from the VTEC signal wire from the ECU. It will connect the battery to the +ve wire of the LED array, thus supplying them with power. It will switch back to its previous state, cutting off the power supply to the LED's when you drop out of VTEC.

The LED array consists of five rows of five LEDs, 25 in total.

The full wiring diagram:


Part 3: Removing the dash

If you know how to do this, skip to Part 4. It's all pretty self explanatory, I doubt you'd even need the walkthrough on how to do it, just undo the screws and remove.

So, first things first, remove the dash. To do this remove the tweeter covers, unscrew the tweeters if there are any and place them to one side out of the way.

Secondly, unscrew the top part of the dash above the smoked screen, it runs all the way from the left to right. Once it has been removed, you can get to the smoked screen on the left part of the dash (with all the warning lights etc and water temp, that part). Unscrew the screws holding it in on the left, there is also one in the centre of the smoked screen. There should be a piece of plastic screwed in between the left part of the smoked screen and the dials unit, with one screw at the top. Undo the screw and remove that piece. Once those screws are removed, unclip the smoked screen and move it out the way.

You should now be able to see the screws holding the dial unit in. Undo all the screws holding it in (there are a few on the right hand side, might be hidden away behind wires). It's easiest if you have a magnetic screwdriver, as some of the screws are hard to get to!

Once all the screws have been removed, you'll need to unclip the cables leading to the dials. First off, unclip the wires connected to the silver box under the drivers side tweeter, this is the power supply for the EL dials bulbs.

There is also a cable at the bottom left of the dials, I think this is for the automatic cars, as on the auto dials Taffy sent me the board the cable connected to was wired to the back of the dials. On mine (a manual car) it isn't. Unclip that cable if it is there.

Now, the cables on the top of the dials. To get them a bit more visible, twist the dials unit, moving the bottom part away from you towards the engine bay, and pulling the top part towards you into the cabin, this should expose the cables a bit more. Using a flat head screwdriver, unclip them (that's what I did, as they're tricky to get to and you know what those plastic clips are like  :roll: ).

Once all the screws and cables are gone, you should be able to remove the dials. Twist it more like you were earlier, and pull it out. Don't be afraid to use a bit of force, it takes ages to get to know how to remove it properly. Now on to Part 3!

Part 4: Dismantling the EL Dials

Now the fun part. If you already know how to dismantle them, then skip to Part 5.

A word of caution here: BE CAREFUL WITH THE NEEDLES. The speedo and tacho needles are very sensitive. I had to get a set of dials off Taffy to replace one of them as I dropped it. For the purpose of this section I am taking pictures of dismantling the dials Taffy sent me as I didn't take any whilst removing mine, and as they're auto dials they have a place for the shift lights, ignore that.

So, now you have the dials out of the car and on the table inside, or in the garage. You'll need a good source of light around you.


First off, remove the screws holding the plastic and metal back plates on. Once those are removed, remove the two circuit boards at the base of the dials. Place them to one side.



At the top of the dials, you'll see the little white cable running from the circuit board for the indicator/high beam lights. Unclip that from the dials. Once thats unclipped, pull the rubber/plastic handle off the trip meter needle. Now you can unclip the smoked screen covering the dials.


The needles should be exposed now. With a very small Phillips head screwdriver, undo the two black screws on either side of each needle.


Now, removing the screen, I find it easiest to push (gently) the needles halfway round the dials as there is a pin at the bottom of the screen that the needles rest on and you can't remove the screen with the needles resting them that. However you remove it, be [i]very [/i]careful around the needles!


Once that is removed you can access the dispersion plates. Remove them, they're easy :lol: (by the way, those squares in the middle, between the needles are for the shift lights, or gear lights or something, for the auto cars. Manuals won't have them, so ignore them  :) )


Now they're out of the way, sit the dials standing up and undo the the six screws holding the needle units in place, three per unit. Remove the needle units. DO NOT PULL ON THE NEEDLE TO REMOVE IT! Very careful pull on its housing to remove the unit. Make sure the case does not rest on the needles.



Now, remove the circuit boards from the back of the dials. Easy enough, just unclip the wires (two to the bulbs, one to the tripmeter needle), then the board is only clipped in around the edges. No screws to undo.

Remove the clear plastic clips holding the bulbs in. Leave the bulbs in place.

Part 5: Preparing the EL Dial Case

Now everything has been removed that needs to be removed and the EL bulbs are exposed, take a sharp pencil and trace around the bulbs. Once that is done, remove the bulbs and place them carefully to one side. The reason we did that was so that when placing the LED's we know where we can and cannot place them.

You can see where I have traced the outline of the bulbs.


So, you've traced the outline and removed the bulbs. Now comes working out where you want the LED's to be set!

This is where I placed them


Unforunately, of the two at the top centre the one on the right had to be moved as one of the indicator lights was there. So I just unglued it and moved it to the other side of the board as I had wired everything up at the point I found this out, and there wasn't much I could do!

Now, once you know where you want them placed, get the drill and the drillbit with the slightly smaller diameter than the LED. Drill a hole in every position you have marked for the LED's (25 positions).

Now, mix some of that two part glue together (I highly recommend using it, it was perfect). Place some of the glue on the dials case around the hole. Make it quite thick, then place the LED into position with the legs sticking out to the back of the dials. We'll cut the legs down to size later.

Repeat for every hole made.


Now, all the LED's are in position and stuck fast. If you look at the LED wiring diagram, you'll see that we have five rows consisiting of five LED's each. So, you'll need to group five LED's together to be wired to each other.



Five groups consisting of five LEDs. Now, you've decided which LED's are connected, cut the legs down so they just stick out of the hole. Make sure theres enough space to solder a wire onto each one but that it doesn't stick too far up to catch the back of the circuit board.

Next, take the voltmeter and test each LED. Find out which leg is positive and which is negative, and put a mark on the case next to the positive leg. Do this for all the LED's and double check! You can mark the positive and negative legs before you cut them down to size (as the legs are different lengths denoting +ve and -ve, I'm happier testing them myself to make sure).

Next, get the wire, cut it down to size and solder the LED's in order, group by group. The negative leg of the first LED will be soldered to the positive leg of the second LED of the group, the negative leg of the second LED will be soldered to the positive leg of the third LED etc. Once you reach the last LED of each group, solder a piece of wire between the negative leg and the resistor.

Once all groups have been soldered independently, solder a long piece of wire onto each +ve leg of the first LED of each group. Twist the ends of these wires together and solder another long piece of wire onto it. This is connecting all the +ve connections of the group together to one long piece of wire that will connect to the relay. Also solder a long piece of wire onto each resistor at the end of each group, also twist the ends of these wires together and solder a longer piece of wire onto this group, this wire will go to the ground point.


In this section is is always a good idea to check constantly that the LED's are still working once you've soldered the wires onto the legs, as the heat from the soldering iron can damage the LEDs and resistors. So once a group has been done, connect a 9V battery to the positive leg of the first LED of the group and the resistor at the end of the group to make sure it works. If they don't light at all, get the voltemeter and test one by one, it could be a dodgy connection, or an LED or resistor could have blown! Also make sure your solder points are solid and that no wires could come loose.

Once all the wiring in the dials is complete and you're happy it works place electrical tape over all the wiring, LED legs and solder points as there is an electrical board being placed over the top!

If you like, you can test that it works properly before closing the dials up. Go to the car, open the bonnet and connect the main +ve wire to the positive point of the battery, and connect the ground wire to the -ve point of the battery, if all the LED's light up, it works!

So, all the LED's are fitted, the wiring is done, they all light up, you've covered all the wiring at the back of the case with electrical tape to stop any shorts and keep it all tucked away, all thats left is to close it back up! Re-assemble the dials, making sure everything is connected properly. Make sure you mark which cable is for the +ve connection and which goes to ground!

Part 6: Fitting to the car

Now the tricky part. Refit the dials to the car, threading the +ve and Ground cables from the VTEC lights down behind the dash to the drivers footwell. Take car not to pull the wire too hard! This is the section I'd recommend using flexible wire and not the wire from Maplins.

In the drivers footwell, solder the MALE part of the spade terminal to the +ve wire. Do the same to the ground wire.


What I did was strip the wire, place it in the terminal with a bit sticking out the end, crimp and then solder the little bit at the end, to be extra safe.


Next, go to the passenger side and fold up the carpet exposing the ECU.


Splice into that wire (its Green with Yellow Tracer).



Wire that into Pin 8 of the relay (female spade terminal or soldered directly to the pin).

Next, cut two lengths of wire to go between the relay and the LED +ve and LED Ground connections from the dials that you soldered the MALE spade terminal onto earlier. Solder the FEMALE part of the spade terminal onto the cut wire and connect the terminals to the LED +ve and Ground wires. This is so that the dials can be easily disconnected from the rest of the circuit if they need to be removed.

Now, take the wire you just worked on that was connected to the LED +ve wire. Solder a female spade terminal onto the other end and connect to Pin 4 of the relay.

Now, thats the cabin work done for the time being.

Open up the bonnet and find the rubbet gromit behind the fuel injection unit by the brake lines half way down the bulk head near passenger side (thanks Bri!)


My pic:


You may need to get a rather long screwdriver and push the gromit back into the hole and down, as I had to as pulling it out didn't work. Next, you might need to repeatedly jab at the hole with the screwdriver at an angle to push the padding out of the way. There was something blocking the top part of the hole, hence the reason to push down. Either way, find a long screwdriver, and push it as far in as possible (do not force it too much! It should slide quite easily). Next, go back into the passengers footwell and try and find where its poking out from. Once you have found and cleared some space get the flexible wire and feed it through. It needs to reach from the battery, around the engine bay into the passenger footwell to the relay. Two lengths are needed, one for the +ve connection of the battery, one for the ground (if you can find a ground point in the cabin, use that instead, I couldn't so I used the engine bay ground point). Once you are happy the lengths are perfect (always allow a bit extra to be safe), cut the wires.

Make sure you know which one is for the +ve and which one is for the Ground point!

Strip both ends of the +ve wire and solder them. Connect one end to the battery, and the other to Pin 6 on the relay (either by soldering it or using a female spade terminal). Choose the location of the fuse holder, and cut the wire at that point. Strip and solder the +ve wire to the fuse holder and affix the fuse holder to the chassis/a cable whatever.


Strip both ends of the Ground wire. Attach one to the ground point (wherever you choose that to be). Twist the other end together with the LED Ground wire from before (the one from the dials). Attach these twisted together points to Pin 7 of the relay and solder (or attach them to a spade terminal and attach that to Pin 7).


Now you should have connected the relay to the VTEC signal wire, the LED +ve wire, the battery +ve (with a fuse between them), and connected the relay Ground and LED Ground points together and grounded them.

Fit the fuse to the fuse holder. This is where I have temporarily put it:


The relay:



The big test! Make sure everything is connected and secured, and that no wires in the engine bay are in the way of anything.

Take the car for a spin  :twisted:

If it works, pack everything away, refit the carpets and secure the relay somewhere safe where the cables won't be caught by peoples feet.

If it doesn't, test each connection point with the voltmeter. Providing you followed the instructions and tested the LED array once it was complete, it should all work correctly!

NOTE: -Always solder each connection! And make sure it is a solid connection. -I used the ratchet to undo the bolts to move the ECU out the way, you may not need to. -I wouldn't attempt this if you're not happy soldering or working with rather vital parts of the car (cutting into the VTEC signal wire for instance!) or don't understand the wiring diagrams above.

If you are unsure about anything in the How To, let me know and I'll explain it better!

Hope you've found this interesting! If you attempt it and get stuck at any point, gimme a shout and I'll try and help.

Thought I'd share a bit of useful info my dad told me about. If you are worried that you're cutting into the right wire (in whatever scenario), what you can do is take a pin, and stick it into the wire until its in contact with the cable under the sheath, wire the rest of the system up and test (obviously connecting a wire to this pin to simulate splicing into the cable). But this is only for short term testing! You cannot leave it like this. Once you have found out its the right wire you must make a proper connection. Hope that ever helps!