Alarm system help needed!!
Discussion
Okay a bit of help needed here in disabling my alarm/immobiliser. My Mx5 track car has been in storage since Feb and having had it delivered to my house the battery was completely flat.
Having replaced the battery it appears some long lost immobiliser system which I’ve never used/knew about has woken up and kicked in. I wondering if it’s some standard(ish) fit device that you guys might know how to work (turn off).
When I connect the battery, all the doors lock (I didn’t know it had central locking) and little red lights come on in the corners of the dash. Getting in the car, the hazard lights flash and I while the engine turns over it won’t spark.
I think the system is sitting on the top right hand corner of the engine bay (red)
There is a cable running over to the fuse box with some kind of cable snake on it with a connection linking to the coil pack which I guessing is what is stopping the engine firing (blue). I’m half tempted to resolder this link and see what happens but before I start tearing my wiring loom apart I thought I would take a few photos and see if anyone knows how to get rid of the thing without cutting wires.
In the cabin I have two buttons:
Pressing them doesn’t seem to do much.
I also found this remote in the ash tray but again pressing button lights the led but doesn’t do much.
I have these sensors in the corner.
Somebody has disabled the sounder at some point by cutting the wire to it.
Taking the black plastic cover reveals this (potentially a relay).
The sticker in the window suggests its a Mazda system but the fitting looks decided fter market (aging electric tap and soldered in wires)
Anyone seen this setup before and know how to turn the thing off? Do I need to press and hold the buttons or should I start splicing the wiring loom?
Thanks for your help.
Having replaced the battery it appears some long lost immobiliser system which I’ve never used/knew about has woken up and kicked in. I wondering if it’s some standard(ish) fit device that you guys might know how to work (turn off).
When I connect the battery, all the doors lock (I didn’t know it had central locking) and little red lights come on in the corners of the dash. Getting in the car, the hazard lights flash and I while the engine turns over it won’t spark.
I think the system is sitting on the top right hand corner of the engine bay (red)
There is a cable running over to the fuse box with some kind of cable snake on it with a connection linking to the coil pack which I guessing is what is stopping the engine firing (blue). I’m half tempted to resolder this link and see what happens but before I start tearing my wiring loom apart I thought I would take a few photos and see if anyone knows how to get rid of the thing without cutting wires.
In the cabin I have two buttons:
Pressing them doesn’t seem to do much.
I also found this remote in the ash tray but again pressing button lights the led but doesn’t do much.
I have these sensors in the corner.
Somebody has disabled the sounder at some point by cutting the wire to it.
Taking the black plastic cover reveals this (potentially a relay).
The sticker in the window suggests its a Mazda system but the fitting looks decided fter market (aging electric tap and soldered in wires)
Anyone seen this setup before and know how to turn the thing off? Do I need to press and hold the buttons or should I start splicing the wiring loom?
Thanks for your help.
Easiest way - cut it out.
If you didn't know it worked anyway, and it's only causing problems, get rid of it.
They only take about 2 hours or less to put in, and the includes drilling for the siren bracket, etc.
It should take you about an hour to remove the whole thing.
Thatcham systems are basically completely covered in black insulation tape, so that it looks 'original' on the car, and not easy to tell (in the dark) where the modifications are. Get rid of the tape, and it'll be a doddle to see where all the wires go.
You'll find the relay is probably the cut-out for either the ignition, coil packs, or if it's a Thatcham cat. 1, both.
Get a soldering iron, find where the loom's been cut, and re-solder back together. Don't use terminal block or scotch locks, soldering is the only way. Heat-shrink if you can, or plenty of insulting tape at the very least. Don't let the damp get in.
Then go through and cut out each wire individually.
You'll have something like;
At a guess, if the siren wire's been cut, it's because it went off all the time. If it's fitted with ultrasonics, it would.
If you ever wanted a new one, they're only a couple of hundred quid fitted, and there's much better on the market now.
To just get it running at all, unplug the siren from the control box (again, assuming Thatcham system), track to the ignition and/or coil, re-solder and seal, and that should do it.
The buttons are probably 'valet' buttons, for turning off the system.
HTH.
If you didn't know it worked anyway, and it's only causing problems, get rid of it.
They only take about 2 hours or less to put in, and the includes drilling for the siren bracket, etc.
It should take you about an hour to remove the whole thing.
Thatcham systems are basically completely covered in black insulation tape, so that it looks 'original' on the car, and not easy to tell (in the dark) where the modifications are. Get rid of the tape, and it'll be a doddle to see where all the wires go.
You'll find the relay is probably the cut-out for either the ignition, coil packs, or if it's a Thatcham cat. 1, both.
Get a soldering iron, find where the loom's been cut, and re-solder back together. Don't use terminal block or scotch locks, soldering is the only way. Heat-shrink if you can, or plenty of insulting tape at the very least. Don't let the damp get in.
Then go through and cut out each wire individually.
You'll have something like;
- 2 x wires directly to the ultrasonics (no idea why they fitted these - convertibles should have a microwave sensor) that can just be unplugged
- Ground wire (normally bolted to chassis)
- Feed wire (normally red - not too original)
- 2 x central locking wires (1 x lock, 1 x unlock - pulse operation)
- 1 or 2 immobilisers to ignition and or coil
- A link cable from the 'brain' to the siren (assuming it's a Thatcham alarm)
At a guess, if the siren wire's been cut, it's because it went off all the time. If it's fitted with ultrasonics, it would.
If you ever wanted a new one, they're only a couple of hundred quid fitted, and there's much better on the market now.
To just get it running at all, unplug the siren from the control box (again, assuming Thatcham system), track to the ignition and/or coil, re-solder and seal, and that should do it.
The buttons are probably 'valet' buttons, for turning off the system.
HTH.
[quote=(steven)]
When I get a minute I'll strip the system out to improve my 'weight saving'.
100g makes all the difference!maser_spyder said:
Interesting stuff
Thanks for that. You were right, it was worryingly easy to get rid of. One redone' electrical connection and a few removed fuses and as good as new. When I get a minute I'll strip the system out to improve my 'weight saving'.
I had a Thatcham alarm fitted to a Supra I bought, then a week later went to the beach and left the keys out in the rain.... Spare keys at home, and remote that disabled the alarm and immobiliser was completely dead.
I managed, in the beach car park with no tools whatsoever, to cut the feed to the alarm system to disable the siren, and re-join the immobilised wiring in about 10 minutes.
Very worrying.
Admittedly, I fitted these for Renault when I was a student, but all the same....
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