This should be in the DIY thread
FYI: This was completed on a 2001 Jetta 1.8T. Changes made to the electrical system from 2002 may make the install and wiring more complicated. Consult a current Bentley and wiring diagrams for YOUR YEAR and make.
Had some free time and a switch so I gave it a try.
Thanks to judoGTI for electrical help and the idea from his old thread .
What follows are the instructions to wire an Engine Start Button in line with the cars keyed ignition. In this setup the Engine Start Button will only work with engine switched to ON. I used an Ignited Performance Illuminate Switch.
IMPORTANT ~Disconnect negative battery terminal. While the majority of the work will be on wires that are switched off it is a good precaution to prevent shorting wires when moving stuff around.
DISCLAIMER I assume no responsibility for damages caused by this modification or errors made by anyone trying this. At your own risks as always.
Remove lower panels and metal panel covering relay panel.
*2 Torx 20 screws per panel (left of steering column, right of column, remove fuse box cover).
*2 Torx 25 screws for metal cover and 4 Torx 20 screws.
Remove steering column cover and disconnect ignition harness on left side.
Bottom portion of column cover cannot be removed without removing the steering wheel.
picture shows extra wiring for turbo timer
*2 Phillips screws under in front (you will need a micro screwdriver to get at them).
*Lift column cover up and use both hands to grasp lower instrument panel trim plate and pull out while holding firmly.
*Grasp ignition harness from behind (side facing instrument panel) and wiggle free. It has two guides and a center clip in addition to the spades.
Remove back clip from harness and pull out ignition wire.
*Back retaining clip (in purple) has four clips holding it. Ignition wire is red w/ black strip for automatic transmission (pictured) and red w/ green stripe or redw/ gray stripe for manual transmission.
EDIT: There are apparently some variation in ignition wire colors. Wire is of thinner gauge on early model years and on the bottom of harness. Check your Bently diagrams to confirm wire color for your year and make.
*Use a skinny metal pick on front face of harness to unclasp both top and bottom metal clips of wire and then pull gently from behind (this may take some work working the pick around and gently pushing/pulling wire).
*Test~Car should no longer start if you have done all correctly.
*Plug metal spade into end of ignition wire. Zip tie both wires to wire bundle (do not zip tie black bracket to the right of ignition wire bundle).
Run wires to relay. (pictured to the left of relay 175) I located relay and completed wiring into the stock relay block with OEM repair wires and a OEM Relay panel, but this is not necessary.
while a relay is not required for the Ignited performance switch to work it is recommended and is good practice to protect components
*Run ignition wire splice to 87 on relay. Run switched power lead to Engine Start Button input. Run a third wire from Engine Start Button output to 86 on relay. Find a 12v power source (I used the same switched power lead) and tap and run it to 30 on relay and ground 85 on relay. Depending on Engine Start Button ground as needed.
*Secure wires to test, reconnect battery.
*With relay disconnected use a volt meter and measure voltage across 12v power lead (30) and ground. This should read ~12v at least when ignition is on (or both if you tapped a constant wire). Measure voltage across wire to ignition and ground. This should read 0v and ~12 when you press Engine Start Button.
*Install relay and attempt to start car. Engine will only start with key in ignition switched to on.
If all is well install switch where desired. If installing in location of cigarette lighter the 12v plug must be carefully removed first.
*1 Torx 20 screw under garbage/ash tray.
*Push entire tray towards front of car to unhook clips from metal retaining strap. Angle and pull out carefully. Disconnect harness for cigarette lighter and remove tray completely.
Metal strap swings up if you want to remove lower center console panel.
12v Plug Assembly Removal
*pull black garbage tray bulb cover off of back side of 12v plug assembly. Press red plastic clips on backside of plug in gently and push from back of plug through opening.
Install Engine Start Button and secure all wiring and your done!
Thanks all Wiring this is actually REALLY easy if you have any know-how. I wired up my fogs OEM style at the same time and the engine start button was easier (read simpler) by far.
Quote, originally posted by nirav » thats a very ideal place to put it. fits in perfectly
Perfect would be if the cigarette lighter ws to the left of the ashtray and not to right. You kind of have to reach around the shifter. Wonder if they have a different tray layout for right-hand drive cars . . .
Quote, originally posted by horsty69 » does it have a backlight for when your int. lights are on??? sweet mod and nice write up
The switch is illuminated when you turn the ignition to ON (regardless if interior lights are on or not). This is how I wired it, but you could wire it to be on with the lights if so desired.
Quote, originally posted by Jenkins » wow cool!
does it by pass the immobiliser code?
It works in conjunction with the keyed ignition so it is not bypassing the immobilizer, just rerouting the source for the triggering of the starter.
Modified by evilpat at 7:40 AM 1-12-2004
Quote, originally posted by Sleeper GM » Nice write up .... so will the car only start now with the start button?
Correct, if you turn the key passed ON nothing happens as the ignition wire (lead that controls the starter has been removed), but the key MUST be in the ignition and in the ON position. This process is very easily reversed by simply disconnecting the spade and plugging the wire back into the harness.
Quote, originally posted by moody18tgti » very nice mod bro...I would have wired it to the interior lighting dimmer tho. I like.
I thought about that but then I would have to have to turn the lights on to see the switch at night (not like I won't be able to find it but I like it). It would be very easy to run illumination from the dimmer switch. In fact there is even a wire on the cigarette lighter harness as it is illuminated as well.
I will be relocating my 12v plug next to the hand brake eventually.
If you want to use an OEM relay plate here are the PNs. Order 1 of each.
443 937 527 Relay Plate
000 979 227 2.5 mm wire w/ 2 connectors (or 000 979 135 1.0 mm)
000 979 114 1.0 mm wire w/ 2 connectors
Any 40 amp relay will plug right into it.
Quote, originally posted by Convallo » Can you still use the key ignition as well?
No, I disabled it by removing the wire from the harness. I guess theoretically you could tap the wire instead of removing it from the harness and both would work but I wanted only the engine start button to function. I will eventually install another relay to disable the engine start button relay when the emergency brake is disengaged as protect against accidents . . .
Damn......I had the same exact idea. I have the button in my ashtray sitting there waiting to be put in actually. I was planning on putting it in the same exact spot as that. I figured I'd be one of the few people if any to have it and def the only one to put it right there. Oh well its still going in there but at least I've got idiot proof schmatic to go by.
sweet What a great mod, never thought of that. One night when your asleep, I'm gonna switch everything around in your car, so that the start button pops the gas cap, the trunk button locks your doors. Gotta do something to slow you down, and quit comin' up w/ these ideas before we do.
Modified by Convallo at 10:23 PM 1-12-2004
As stated above this process is very easily reversible by simply plugging the wire back into the harness, bypassing the button and allowing the keyed ignition to function.
If you would like to be able to do this quickly you could replace the ignition wire in the ingnition harness with a repair wire (with correct connector for harness) with a spade connector on the free end so you could easily connect and reconnect the ignition wire without removing the harness repeatedly. Of course this makes it easier for someone to run power to the ignition (given they have gotten around the immobilizer and the keyed switch) If you need help with the wiring just let me know. I might even be able to make up some harnesses . . .
Modified by evilpat at 12:23 PM 1-13-2004