Topic

Del, the clockspring, formally known as the rotary coupler is a completely different thing, unrelated to starting the car or security., It provides physical electrical connection between the wiring loom and the electrical items that turn with the steering wheel such as the horn buttons & driver's airbag. {& shift controls on Stepspeed automatics].
It consists of a spring loaded multicored wire on a spool which sits just behind the airbag. You may have seen it mentioned in relation to diagnosing SRS airbag warning light faults.

Great, got that now, thank you all.

Early cars didn’t have the exciter ring around the lock barrel, although the electronics had the capacity to utilise the system. They also had the corresponding device (referred to as THE CHIP) in the key to enable the ring.
Without the ring it could be a right old palaver, with various lockouts coming into play after a time, causing you to turn things off & go right back to being able to start the car.
Fitting the exciter changed that in an instant without software updates.
And once you have identified the module to interlink with the coil, the pin numbers on the module sorted out, suitable contact inserts, compatible with the factory fit headers & an extension wire fitted to the ring, it’s plug & play. (!)
M

This information is very interesting. Thank you.
Is the exciter ring also present and operating in later cars (with MEMS3).

Presumably all that complexity and dependence disappears when the ECU is remapped

generous_dad wrote:

This information is very interesting. Thank you.
Is the exciter ring also present and operating in later cars (with MEMS3).

Yes, cars with MEMS 3 have this feature.

It is wrong to assume but presumably re programming the MEMS3 and thereby affecting the interaction with ring around the ignition switch has no effect on the “burglar alarm features”?

One thing about all this pointless security bollocks, is that once someone would just break in and hotwire the car and be gone, but now since they’ve made cars hard to pinch so now the scumbags now resort to one of the following options: kill or maim you in a carjacking, kill or maim you whilst mugging you to get the keys in the car park, or kill or maim you whilst breaking into you house to steal the keys and anything else they fancy!
The young folk don’t bother learning the skills of the thieving trade like they used to.
So in the good ole days they just stole the car, now in these more secure times they get to kill you in the process of stealing your car….that’s progress….. my point is that cars are still getting stolen, only the methods now are more risky of the owner.

Locks and alarms only keep out honest people! The bad bastards always find a way

Delbourt wrote:

It is wrong to assume but presumably re programming the MEMS3 and thereby affecting the interaction with ring around the ignition switch has no effect on the “burglar alarm features”?

Yes, it is wrong to assume that. If passive immobilisation is removed from your engine ECU, that means you do not need your fob to start the engine. That also means somebody can break into your car by smashing window and hot wire your car and they are gone. Yes alarm should sound because opening door will triger alarm, but then just depends how quick they can hot wire your car and be gone.