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Discussion Starter #1 (Edited)
Tracker Installation E36 – Vehicle Used E36 323i (October 1997 Build)

This guide convers installation of the ‘generic’ TK103A GSM/GPS tracker, although if you purchase a similar one this guide will be helpful I’m sure. I am an electrician, work with a lot of fine electronics and have been doing vehicle wiring for many years so I take a belt and braces approach toward this, if you think I’m being too finicky please use your own judgement and cherrypick precisely what you’d like to do. It’s your car, all said and tolled.

Features of this tracker:
- Full GPS tracking by SMS message with no service subscription, the unit will accept any 2/3G SIM card designed for use in the UK.
- Immobilizer, albeit a very simple one but it might be enough to deter the local kids from having a go.
- Anti-hijack, this is brilliant, you can text a secret word to the car and it actives the immobilizer with the engine running, leaving the scrote in an awkward situation.

Items Required:
- TK103A Generic GSM/GPS Tracker, I purchased mine from for £21.99
- A ‘generic’ 2 way automotive fusebox (not required, see further down)
- A SIM card, PAYG is probably the best option as you’ll just need a smidge of credit to text the unit theoretically. This is discussed below too.
- A DECENT ratchet crimper tool sutable for automotive type crimp-on terminals.
- Knife, wire strippers, self tapping screws.
- Soldering iron, heatshrink tubing and plenty of good quality insulating tape.
- A multimeter (a basic one is just dandy.)
- Sand paper or a small file
- Small cable ties
- Screwdrivers, sockets, spanners (just a basic selection)
Useful, but not vital:
- Ferrule putteronerer tool (no idea what the proper name is)
- Pop rivets and tool
- Powerdrill, selection of small drill bits, glanding tools, grommets, small hole saws.

A note on tools;
I’m blessed with a toolbox full of nice ‘professional’ level tools but you don’t need these the most humble Poundland screwdrivers and spanners won’t be any less effective for this job. One note of caution however, crimp tools. These tools are effectively useless:

I mean, really, totally useless.

Correct type.

Treat yourself to a set of ‘ratchet type’ crimpers, the plier type are not strong enough to form a patent connection and they have a nasty habit of deflecting about the pivot which is pure frustration. Today sell a Draper ratchet crimper for £15.19 with free delivery which will last a lifetime, and you’ll recoup that quickly in terms of needing far less terminals due to the plier type tool wrecking them. Otherwise, beg, borrow or steal a decent set.

Everything else, feel your way through. I'm using a fancy pair of multimeters here, and whilst I can't stress enough that a battered old-of-calibration Fluke that's covered in grease picked up on eBay for £25 is tons better than a £5 one, the £5 one is equally as useful for this job. Invest in an old Fluke even if it is a bit scummy if the budget will allow, they are faithful old friends that last forever and auto-ranging versions are a Godsend! This tatty meter of the right was an eBay find, the calibration is seventeen years out of date but it's fine for automotive use, the £5 one on the left though does the job admirably.

Final Word
You are responsible for your own actions and this guide is provided for education and entertainment purposes only. I am NOT a qualified autoelectrian and please seek guidance from a suitably qualified individual before commencing. By following this guide you accept all implications that may arise and this guide may contain errors and omissions.

I only use metric wire sizes (because it's 2015, I'm in Europe, and because they make sense) I've bracketed AWG (American Wire Gauge) if you insist on using that but please double check all cable sizes.
Got a decent set of ratchet crimps? Yes? Let us commence!

1) Get the car in a position where you can have the the two front doors open, trust me, you'll be frustrated if you're working through a six-inch gap to get in to the footwells.

2) Remove the glovebox, you'll need a cross-headed screwdriver and a 10mm socket and ratchet. Firstly remove the two screws in the top left/right hand corners of the ventilation vents and pull away the upper panel.

Working around the glovebox remove the four screws, two are situated under the small caps which are prised away with a small screwdriver.

Remove the 10mm headed screw in the top of the glovebox but removing the lamp (prise away) and disconnecting the wiring. The screw is located under the lamp fitting. Ease the glovebox out and put it aside.

3) My preference is now to mount the unit, that way the cables can be neatly arranged and you'll be far less likely to tie the cabling up in knots or go to refit and find it running through an aperture. I've chosen this spot here as it's nice and discreet, doesn't impinge upon anything and means a lot of the cabling can be cut rather short.

I've used pop-rivets to try and confound anybody who finds it the tracker a touch more as the unit will need to be drilled out, however small self-tappers or even adhesive tape could be used. I've drilled two small holes, and with a couple of small washers pop-riveted the unit in.

I've also installed the small fusebox, with a jumper wire, you won't need to do this (I'm installing two modules to the car but that will be covered in another guide, this gives me two neat power-sources) and also mount the relay, be as discreet as you want here but consider cabling!

4) Wiring STEP ONE.
Before much else can happen we need to energise the circuit whilst providing a small secondary feed to the relay. At this step we're concentrating on just a 12VDC and 'Earth' (0VDC). Firstly let us find an earthing point, this is essentially any vehicle metal work but we've got a handy-dandy point here that just needs a ring terminal.
For the unit plug the cabling in and route it as neatly as possible around to the earth point (allow an inch or two slack incase the termination goes wrong,) cut the cable and using your DECENT tool strip and fit a ring terminal to the end of the cable.

Grab a length of black automotive grade cable (around 4mm-sq/10-12AWG is ideal) that is long enough to reach from the earth point back to the relay, route this neatly back to the relay and leave a few inches either end. Fit another ring terminal to the earth end, for the time being just leave the other end un-terminated near the relay. We'll come back to that.

Now located a 12VDC permament power feed, we're only going to be drawing a few mA so it's unlikely that we'll pop any fuses but exercise caution. I've used [TRACE] [CIRCUIT] as shown here as this is constantly live and the circuit will accept another draw of a few mA without any issues. Heat up your soldering iron at this point!

Ring off about 35mm of insulation and reveal the conductor underneath, now push the conductor in on itself to splay it open.


Neatly fit and trim the +12VDC cable to the tracker down to the point it will terminate to the cars' wiring and cut back about 30mm of insulation.

Wind the tracker cable through the gap in the vehicle cable and tightly wrap it around as shown:

Tap a small about of solder across the connection, less is probably more here and check the wires are still visible, the solder is meant to soak in through the cabling NOT sit on top of it. Get the iron nice and hot and leave a bit of revealed copper at either end.

Allow it to cool then tightly wrap it in insulating tape. If you've never soldered before or your skills are a bit rusty practice first on some scrap in the shed beforehand. This should be a very secure connection as good electrically as the BMW factory cabling.

Now remove the nut, slide the two ring terminals on to the stud and nip down securely. Refit the tracker fuse, and the LEDs should illuminate.

5) Have a cup of coffee, tea, a cigarette etc.

6) Relay wiring.
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