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Discussion Starter · #1 ·
I have an interesting problem, i'm speaking to a dealer about
an MKIII. The dealer tells me that the Alarm Module is missing
and therefore the vehicle will not start.

Now I have no idea why it's missing, but could anyone point me
in the right direction to bypass the starter kill on this car. I can do
soldering/wiring, but I just can't find a wiring diagram of the
alarm module connector, therefore I'm unable to get this vehicle
started (and no I don't want to push start it to get back home).

I repeat, there is -no alarm module-, but there was a factory
alarm on this car. the alarm module is missing, I need to know
how to BYPASS this alarm module to enable the starter relay.


Discussion Starter · #3 · (Edited)
I have a diagram of the wiring of the alarm system.

From this diagram, the best I can tell is that the starter relay
has two wires going to it. (being a relay, meaning a magnetic

the wire to the far left (of an unknown color, I can't read the
code, O I believe) comes from the ignition switch start position,
and goes through the relay to the starter (M/T) or the neutral
start switch (A/T)

the second one comes from the clutch start switch (M/T) or the
ignition switch start (A/T), passes through the relay, and goes
to the theft deterrent computer.

this is coded L-O (blue orange) and is wire number 13 on the
theft deterrent system.

Now most of the wires on the alarm module (which is what the
theft deterrent system is) go to doors and latches to disable
the system. However, Wire 6 (V-L, Violet Blue) goes to the alarm
horn; Wire 2 (G-W, Green White) goes to the security lamp in the

alright, so here's how it works in a USA spec wire loom with a
manual transmission; the MKIII at least.

You get in your car, put the key into the ignition, depress the
clutch and turn the key to start.

what happens is, you're closing several circuits. turning the key to
'start' puts approx 2 amps and 12 volts down the starter relay wire,
this goes to the clutch start switch; (if closed) then goes to the
starter relay (a magnetic switch) passes through and goes to
the theft deterrent computer.

what happens from here, the computer already knows since you
entered the vehicle weather or not the alarm is active. if the
system is not deactivated, the computer does not ground the
starter relay wire (the wire coming from the starter relay to
the alarm module) thus the current does not get to the starter
relay, and the switch does not close.

but if your alarm is deactivated, the alarm module grounds the
starter relay wire, current travels down this wire, from the
battery to the ignition switch, to the clutch start switch, it goes to
the starter relay; the relay is preety much a magnet; the current
draws the starter relay switch closed, current passes from the
battery to the relay to the starter by another set of wires, and
the engine turns over.

so how do you bypass the starter kill? well if you're like me and
you need a reason to do so (the alarm module isn't present in
the car, missing/stolen whatever); you ground wire 13, the blue
wire with orange stripe, to a suitable non-painted part of the
chassis, this permanently closes this end of the circuit. now
the alarm module can't kill your starter relay.

However, if you do not completly disconnect the system, and
the alarm module is still armed, the horn can sound. if your
alarm module is present and working, and you just have dirty
keyways or whatever, it's not reccomended that you ground
out this starter relay wire; as it preety much destroys the effective-ness
of the alarm module, besides being a noise maker.

each vehicle is different. I used diagrams for two different
vehicles, one makes reference to a door lock control relay and
the other, doesn't. both are for the mk3 I believe, just different
year models of it.

the graphics I used:

Now this isn't a forumla for stealing the MK3. I've just noticed alot
of people have these alarm troubles and they're looking for a way
to bypass it all together. I encountered a whole lot of confusion
from others who made assumptions with no hard proof. wiring
diagrams allowed me to draw my own conclusion. It's your job
to find out where the alarm module is located, and i'm betting
it's not in an easy-to-get spot. Each car is different, and I offer
no gaurentee that this explanation to the solution will work for
you; instead, i've provided wiring diagrams that show they
work. If you don't feel comfortable enough to do something like
this, then don't!

The worst thing you can do to a vehicle is go blindly hacking
away at the wires. One thing you have to remember is that
every componet in a vehicle may have many different obstacles,
but they all come back to a single wire. There's no sense in
trying to bypass something by hacking away at a bunch of
wires, when you can just trace them using a wiring diagram and
bypass them all eaisly, and cleanly enough to where it's quickly

I hope this helps.

Not ur jizz, not ur bizz
6,571 Posts
somewhat of a thread ressurrection here..but skuzzah..did your car just crank and not start..or it did neither all together?

im having a damn problem with my car where it will crank over but not start cause im not getting any spark and i cant figure out why.

i bought the body from someone else with my engine. I locked the door and i notice the alarm light didnt go this thread grabbed my attention in an attempt to hopefully solve my problem.
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