The E30 Aftermarket Alarm Installation Writeup

[84driver]

Hello all,

Here I'll be documenting the installation of a new aftermarket alarm for my E30. In my case, I went with the Scytek Galaxy G20 after reading countless reviews and recommendations. There are many tips and short writeups on the E30 alarm installation, but I haven't found them all in one place. I will attempt to do that here. This post will be continually edited as I go through the process.

My '84 318i is parked right now while I wait for new calipers and rotors, so I thought this would be a good time to document this project correctly.

Goal -- Properly wired reliable alarm installation with many features enabled, including:
Lock/Unlock
Door(s) sensor
Trunk sensor
Dual-stage shock sensor
Siren
Valet Switch
Mount LED with OEM look
Dome light supervision on unlock
All parking lights flash with lock/unlock
Remote trunk release

And as a bonus I plan to add:
Radio and window switches remain active until door is opened

Supply List:
Scytek Galaxy G20 (~$35, internet)
4 Automotive relays (+3 for Accessory-until-door-open feature) ($5-7, electronics supply such as Radio Shack)
1 1A 50V rectifier diodes ($1/ea, electronics supply) (+2 more for retained accessory power)
2 6A 50V rectifier diodes ($1.50/ea, electronics supply)
DEI 524N 2-wire door lock motor kit (~$15, internet)
Wire Stripper, Crimper, Quick Disconnect Terminals (for relays), Pack of butt connectors, lots of wire (auto parts store or electronic supply if you don't already own these things)


Link Collection for the guide:
R3vlimited Links:
Mount the siren under the battery tray and feed the wire through the firewall
Installing the starter kill is not recommended
Green wire (door sensor) on Scytek goes to brown/purple in kickpanel
G20 needs relays for lock/unlock or it will self-destruct (most alarms can't handle the 1.2A needed to trigger the door actuators)
Some E30s have 'delayed entry module' relay that can be used to activate the dome lights (mine does not have this feature)
How to wire the horn with a relay
How to wire the door lock/unlock relays
How to wire the dome light relay
Aux fuse box

12Volt.com Links
Wiring detail for my 1984 318i
Isolate the trunk pin with a diode for use as the trunk sensor
Retained accessory power
Wiring the 2 parking light circuits with relays (More costly than the diode method)

Other links:
E30 wiring schematics
Crutchfield alarm installation tips
Shock sensor mounting tips
German alarm suggestions
Wiring both parking light circuits to flash by using diodes
Example installations of the DEI 524N trunk release
Wiring a new fuse into the aux fuse box [PDF]
Hood pin installation suggestion
More about the delayed entry module and how to retrofit
Electronics parts stores in the Seattle area



Wiring diagram from the Scytek G20 manual



My Scytek to E30 Wiring diagram
This diagram drawn with QUCS free circuit diagram softwares (Windows download here).
Sixth edition of the alarm wiring diagram. This edition has 1A and 6A diodes.
(This diagram is without the retained accessory power.)



Forgot to take a photo of the new G20 before I prewired it, so here's the complete package with prewiring:
In this photo you can see the valet switch and LED with wiring coiled on the left. Siren is on the right.
One of the reasons I chose the G20 is that the remotes look clean and modern - most inexpensive alarms have hideous remotes, and the remote is the only part of the alarm everyone will see. Although I wanted a deal on an alarm I didn't want it to look, feel, or perform cheaply. The remotes are shiny and look durable, and the LED is bright.




And here are the prewiring photos:

1. Wiring 6A50V rectifier diode for one of the parking light circuits
Diodes are one-way valves for electricity, electricity only flows toward the direction of the silver band. I trimmed down the diode leads and used butt connectors because they are less prone to damage from vibration than if I had soldered. Also it was easier and I have a ton of connectors. Don't forget, before you tape mark the tip of the butt connector that is on the same side as the silver band so you know in which direction to wire it!

2. Both sets of parking light diodes
The 6A50V rating means that each diode can handle 6 Amps of current, and that it will take at least 50 Volts of electricity in the wrong direction before the valve will be overcome. Each of the parking light circuits is ~5A (if you look at the Scytek's parking light wire it has a 10A fuse for all the lights).


3. Parking light diodes wired in parallel
You can see my black marks on the end of the butt connectors in this photo. The current will be going from left to right. I used 16 gauge wire throughout this project, which is sufficient for up to a 15A load.


4. Parking light diodes connected to the Scytek wiring


5. Parking light wiring safely wrapped up


6. Testing continuity of the parking light circuit with the multimeter (Ohms)
Testing the high resistance of the diodes in the 20,000 Ohm range.


7. Testing continuity of the parking light circuit with the multimeter (Diode)
Testing the high resistance of the diodes using the multimeter's diode test function. I did check each set of diodes although that is not shown.


8. Wiring the relays to ground
Each of the relays terminal 30 wired in parallel to ground


9. Wiring the relays to 12V
Each of the relays terminal 85 wired in parallel to 12V.
Also shown (from left to right) are the dome light supervision, lock, and unlock wires from the Scytek.


10. Wiring the relays to the Scytek
The dome light supervision, unlock, and lock wires from the Scytek connected to the relay terminals 86.


11. Wiring the Scytek door trigger to same circuit as the dome light supervision relay
The green door trigger wire is on the same circuit as terminal 87 of the dome light relay.


12. Relays shown from top


13. Terminals 87 from the relays
Terminals 87 labeled for connection with the 318's wiring circuits.


14. Tape off unused wires
We won't be using the orange (starter kill), brown (horn trigger) or purple (door trigger positive) for this install, so cut and tape them off and coil them neatly.


15. Wiring one 3A50V rectifier diode for the trunk trigger
The trunk switch also activates the trunk light, so the circuit must be isolated with at least a 1A12V diode. Again I put the black mark on the butt connector to show the direction of the diode before taping.


16. Testing the continuity of the trunk trigger circuit
The blue trunk trigger wire from the Scytek, connected to the diode, tested with the multimeter's diode test function.


17. The Scytek Galaxy G20 shown prewired as in the circuit diagram.


Continue on to the install photos on post #38...

More edits to come...

[rares]

nice work, can't wait... good luck

[StereoInstaller1]

Wow, hell of a 1st post!

Lets see some pics.

BTW: I generally put the siren under the battery tray, kind of tucked into the corner. You can easily run the wires through the DME grommet, virtually invisible.

I see you plan on retained accessory power as well...that is a fun one, mine has that too. I also suggest domelight surveillance, I love that feature. I wish the Scytek had the ability to turn the domelight on when the key shut off, but they cannnot. I have bitched at Arrmen many times about that, and not having a users guide in Spanish...

Hope your pics are better than mine!

Luke

[84driver]

Quick replies! Alarm photos coming soon, but here's my UnofficialBMW build thread. And thanks for the tips StereoInstaller1, I'll be referencing many of your suggestions that I found across the boards.

[StereoInstaller1]

Thanks, bud. Somehow, I have never joined Dales board...even though I have done quite a bit of work for him! Do you know him personally? Have you seen the install in the X5?

[84driver]

Somehow I haven't met Dale in person yet, although my 318 was his first bimmer years ago! I hope to meet up with him as soon as my brakes are finished.

I'd like to see an X5 install. My gf reallly wants an X5 as her next car, I think my E30 got her hooked on BMWs :)

[DaveSmed]

Hey cool, some of my ramblings are linked even.

Let me know if you need any more help with the stuff I was mentioning with the domelight delay relay.

[RobertC]

Luke, this is Barry (reelizmpro). So the heat from the exhaust isn't a concern when placing the siren under the battery tray? M3's get pretty hot in that area.

[StereoInstaller1]

Barry, I have never had one melt ever...but the Scytek siren is small and triangular, so it "tucks" nicely. I even use existing screwholes to secure it.

[StereoInstaller1]

[ninjaotter]

I will be watching this thread with great interest!

[84driver]

Updated the first post with the inital wiring diagram. Took a second to get familiar with QUCS diagram software but it works well. Unfortunately it doesn't allow me to pick a color for the wires, so I'll have to color it separately.

I haven't included the remote accessory power yet, I'm thinking the radio + window motors together will draw a lot of amperage, and should be on separate fused circuits?

Thanks all for the warm welcome! If anyone sees a mistake please let me know.

[StereoInstaller1]

You show a door lock actuator, that will not be needed unless the car is manual locks.

[84driver]

I'm going to attempt to use the DEI 524N to push the nub on the trunk lock, causing the lock to open as if I had pushed in the button -- therefore, remote trunk release! My plan is to mount the 524N vertically next to the current trunk lock actuator... the 524N should arrive early next week.

Won't work if the trunk is double-locked, but since I'll have a trunk sensor I won't (hopefully) need the extra security of the double lock. Are there any E30s with remote trunk release installed? I haven't been able to find any examples.

[DaveSmed]

That diagram is sweet! I'm gonna take a look into that program. (EDIT: ah damn, a tarball. The computer that uses that is currently broke.)

Anyway, here's a way to save a relay and use crap that's already in the car.

The interior light timer control is a relay with a timer inside. It's the thing that clicks behind the drivers kick panel when you cycle the drivers doorjamb switch. If your car is like most E30s the delay probably does not work anymore. That is usually due to a faulty exterior door handle switch, as BMW wanted the domelight to stay on only when you were entering the car, not exiting.

Enough of that crap, how to make it work. Hook the domelight supervision wire into the Brown/Yellow wire on terminal TK (highlighted) from the drivers door jamb switch. That will allow the alarm to trip the timer control relay just like the drivers door does currently.

As a matter of laziness, tying into the output of the timer control relay, the Brown/Violet wire on terminal A (highlighted as well) is a convenient way to pick up the rest of the doorjamb switches for the door trigger input.

Super fun bonus part: If your delay doesn't work, splice the Brown/Green wire from the (likely deceased) exterior door handle switch into the Brown/Yellow wire from the doorjamb switch. It will probably work now.