The £100 Immobilser Solution

[ChimpOnGas]

Here's another option for those on a budget looking to solve their immobiliser issues.

http://motogadget.com/en/electrics/rfid-ignition-l...

Bypass the Meta on the ECU & problematic starter solenoid circuit and run them both through the m-Lock.



The m-lock is a contact free digital ignition lock with RFID designed to switch a relay or relays; so in our case ECU & starter solenoid relays, obviously you'll need to add a starter solenoid relay as TVR didn't fit one originally.



Hide the m-Lock control unit in the steering wheel cowl and wire up the bypassed circuits through it, then pop the battery free fob on your key.

Let the m-Lock replace the dying immobiliser function of your Meta unit without disturbing the system & its locking/unlocking & alarm functions.

And because it works on proximity there's no need for the annoying second press of the Meta fob to start the car if you're not quite fast enough, it'll work like this:

Get in - turn the key - drive away

[shake n bake]

Seems good, do you have one?

[ChimpOnGas]

shake n bake said:

Seems good, do you have one?

Not yet, but I'm seriously considering it.

Actually I've just discovered it toggles between on & off each time you present the fob to the sensor, so if you kept the fob half on your key you'd want to mount that sensor part away from ignition switch or it'll be turning itself on & off all the time.

In many ways a simple latching switch would be just as effective and a damn sight cheaper.

But the m-Lock is a very secure system.

[Sardonicus]

I would rather just fit one of these a known reliable unit (I speak from experience) and not hard to install either spares widely available but seldom needed unless your a key fob abuser (this is a bargain price too) http://www.ebay.co.uk/itm/Cobra-A8510-Thatcham-App... No Mickey Mouse stuff here if your going down that road your better off just fitting a hidden toggle switch

[ChimpOnGas]

Sardonicus said:

I would rather just fit one of these a known reliable unit (I speak from experience) and not hard to install either spares widely available but seldom needed unless your a key fob abuser (this is a bargain price too) http://www.ebay.co.uk/itm/Cobra-A8510-Thatcham-App...

Looks good, and like you say... cheap as chips (no RFID punn intended)

Sardonicus said:

No Mickey Mouse stuff here

Not sure I'd call RFID Mickey Mouse, its used on just about every car made these days, so universally accepted and well proven.

And its been in cat flaps for years

Sardonicus said:

if your going down that road your better off just fitting a hidden toggle switch

Agreed, its hard to beet a simple switch for simplicity and reliability, hard for a car thief to beat it too if they don't know where it is

For total convenience & the ultimate simplicity the best switch to use would be the ignition switch, then just add a hidden interrupter switch for the security aspect.

[zacherynuk]

Has anybody had their chim nicked ?

The immediate hurdles for Joe Bloggs are opening the door... selecting reverse... then getting out later on!

The V8 is also substantially louder than the alarm....

[ChimpOnGas]

zacherynuk said:

Has anybody had their chim nicked ?

The immediate hurdles for Joe Bloggs are opening the door... selecting reverse... then getting out later on!

The V8 is also substantially louder than the alarm....

^^^^^^^Wot he said, all good points^^^^^^

[brett84]

this is handy as i've just removed the original immobiliser and fitted a started relay for push button start

[SILICONEKID345HP]

brett84 said:

this is handy as i've just removed the original immobiliser and fitted a started relay for push button start

Which part of the system opens and closers the doors . If i could have it my way I would rip it out and fit a switch .

Just don`t know how .

[ChimpOnGas]

SILICONEKID345HP said:

Which part of the system opens and closers the doors . If i could have it my way I would rip it out and fit a switch .

Just don`t know how .

There are two units which are paired together so must be replaced as a pair:

1. The alarm unit

The alarm unit is responsible for triggering the central locking relay, pulsing the indicators on lock/unlock & firing up the siren if the microwave sensor sees an intrusion or the door switches are activated when the alarm is armed, - this unit is pretty reliable.

2. The immobiliser unit

Unsurprisingly responsible for immobilisation, in the case of our cars this unit manages two circuits, the ECU & the starter solenoid.

This unit is pretty reliable on the ECU circuit because firstly it doesn't carry many amps, and secondly because TVR used the Range Rover engine & ECU loom so they also inherited an ECU relay. The existence of this relay has nothing to do with good planning on the part of TVR, it's there because (unlike Dorris at TVR) the boys at Solihull understood how to wire a car properly.

The problems start because for whatever unfathomable reason TVR decided they didn't actually need to fit a relay to the starter solenoid circuit, which is nuts if you think about it as it draws a lot more amps than the ECU and every other modern car would always have a starter solenoid relay to take the load off the contacts on the ignition switch. TVR simply passed all the starter solenoid amps directly through the Meta immobiliser and its little low amp switching relay.

This little switching relay really wasn't designed for all those amps so the contacts get fried leading to failure characterised by the common no cranking problem even though you've disengaged the immobiliser, fired up the ECU which in turn runs the fuel pump.

People press the key fob and hear the fuel pump buzz and assume the immobiliser is working correctly, the reality is it's only turned the ECU on (which then fires up the fuel pump), the starter solenoid contacts inside the Meta immobiliser are stuck due to years of high amp damage so the starter solenoid circuit is still not being made, hence the no cranking problem.

This often happens when the car is hot because resistance in any electrical circuit goes up dramatically when its hot so if things are a bit marginal that's when you'll get the problem. We now start to refer to the problem as the "hot start problem" at which point we may buy & fit a "hot start kit" which is just the starter solenoid relay TVR should have fitted in the first place.

The problem with doing this is the "hot start kit" doesn't fix the damage that's already been done to the little switching relay inside the Meta immobiliser which has suffered years of coping with the level of amps it was never designed to take.

It's my belief the hot start problem should actually be renamed the Meta immobiliser problem, you may effect a temporary repair by fitting the "hot start kit", but because that circuit still runs through the already damaged Meta unit it should never be considered a permanent solution. If on the other hand you fit a new Meta immobiliser and then add the relay TVR should have fitted in the first place you'll likely enjoy years of reliable service from your new immobiliser.

If you're not fitting a new Meta immobiliser which as previously stated has to be fitted with a paired alarm unit at the same time, then your only practical solution is to bypass the immobiliser on the starter solenoid circuit completely.

At this point you should also fit that starter solenoid relay that TVR neglected to. After completing the bypass what you'll find is the car will crank on the key without disengaging the immobiliser, but the car still wont start until you hit the key fob to fire up the ECU and subsequently the fuel pump. So the car can still be considered secure as its still immobilised on the ECU circuit.

Bypassing the starter solenoid is as simple cutting a few wires and running them through the low amp switching side of your new 40amp starter solenoid relay rather than your failing Met immobiliser, you can easily find these wires using a test meter. Establish a reliable earth for the negative side of your test meter then ask an assistant to hold the key in the sprung start position while you test the bunch of all black wires coming out of the immobiliser with the positive probe of your meter.

When your meter reads 12v get an assistant to cycle in & out of the sprung start position on the key to double check you've located the correct wires, you should see 12v on the meter then 0v, then 12v again ect ect. You have now found the starter solenoid circuit but remember the immobiliser is just a switch, the starter solenoid circuit is looped through the Meta unit so there's an in & also an out you need to find.

These in & out wires are the ones you need to cut, fit spade connectors & put one wire on terminal 85 & the other on terminal 86 of your simple make & break 40amp relay.



http://www.autoelectricsupplies.co.uk/product/169/...

Test by putting the key in the sprung start position again and you should hear the relay click as the low amp switching side you've just connected energises the relay coil and pulls in/connects the high amp side of the relay. All you now need to do is to take a some higher amp cable from the battery to pin 30 on your relay (also a good idea to fit a fuse inline here), and then a second run of the same high amp cable from terminal 87 to the spade terminal on the starter solenoid at the starter motor.

You should now be able to crank the car on the starter without pressing the key fob, this confirms you've completely bypassed the Meta immobiliser. Now switch the key to the off position, back to the on passion, and then press the key fob. At which point you should hear the ECU has come to life by virtue of the fuel pump buzzing for 3 seconds to prime the rail. Then simply crank the car as normal and the engine should start.

No more so called "hot start" issues and no need to expensively tear out the whole paired alarm & immobiliser system, which in practice is probably all functioning fine apart from the one problematic starter solenoid circuit running through the immobiliser unit.

You should end up with a car that starts first time every time and all for the cost of a simple relay, an inline fuse holder, some cable and a few connectors. In fact if you follow the instructions you should be able to complete the bypass in 30 minutes or so for less than a fiver.

Dave.



NB: To keep the nanny state happy I've not revealed the location of the two Meta units, but it doesn't take a genius to find them

[brett84]

I removed the standard immobiliser, because i'd changed the ECU I had already bypassed two of the circuits and the circuit which works on the starter was a joke. Take off the steering wheel cowl and you can see where they had joined in the immobiliser wires, would have took about 30 seconds to bypass it. And i HATED the little nipple immobisler key thing (early car) Fitted my own security instead

What I ideally want, and am looking for is an alarm with this contact technology built it, so on your fob there are maybe 4 buttons. Not bothered about going full keyless as i'm guessing it gets expensive and you have a steering lock to disable with the key anyway

1 - alarm on/off as a manual option
2 - driver door 'pop'
3 - alarm activated without interior sensors for when the roof is off
4 - book release

Then you just need one key, one fob. Get near, press button to open the door, key inserted for steering lock and then press button start.
I haven't been able to find something which does this though?

[ChimpOnGas]

brett84 said:

I removed the standard immobiliser, because i'd changed the ECU I had already bypassed two of the circuits and the circuit which works on the starter was a joke. Take off the steering wheel cowl and you can see where they had joined in the immobiliser wires, would have took about 30 seconds to bypass it. And i HATED the little nipple immobisler key thing (early car) Fitted my own security instead

What I ideally want, and am looking for is an alarm with this contact technology built it, so on your fob there are maybe 4 buttons. Not bothered about going full keyless as i'm guessing it gets expensive and you have a steering lock to disable with the key anyway

1 - alarm on/off as a manual option
2 - driver door 'pop'
3 - alarm activated without interior sensors for when the roof is off
4 - book release

Then you just need one key, one fob. Get near, press button to open the door, key inserted for steering lock and then press button start.
I haven't been able to find something which does this though?

That's what I want too, a RFID in the steering wheel cowl and a chip in the key would be the answer.

I'm not bothered about a start button function, but immobiliser deactivation really shouldn't require pressing the fob a second time if you miss the ridiculously short window of time the Meta system gives you to turn the ignition on.

I thought the m-Lock would do what I was looking for and in a way it does, but the fact it toggles from on to off each time you present the fob means it's still a faff.

In the end a complete bypass on both circuits running the ECU one through a simple hidden switch seems like the most logical & cost effective answer.

Sometimes the simplest solutions solutions are the best

[brett84]

yep