5 replies to this topic

[simonlpearce]

How does the immobiliser work? I read the following on wiki answers but it was a more generalised overview...

http://wiki.answers....r_work_in_a_car

there are a number of types of immobilizers for automotive use. Many new cars come with them installed from the factory, and in those cases the actual electronic control unit for the engine comes from the factory with an immobilizing circuit that will prevent the fuel pump and usually the ignition circuit as well from operating unless a transponder device is within the range of the sensor. These are the best type of immobilizer in terms of safety, because they are not a separate electrical circuit which can be easily tampered with like aftermarket systems.

Is it possible this is the reason for my non-starter? I have no pressure at the fuel rail...

Edited by simonlpearce, 19 May 2011 - 08:19 AM.

[slindborg]

No. Cars from say MY2000 onwards will have 'key through' immobilisers that let you start the car faster and then kills the engine if the immo isnt happy (or carry on if it is) For the record that Wiki page is a load of toss.... it pretty much outlines how to wire up an aftermarket immo and NOT how OEM ones work.

Edited by slindborg, 19 May 2011 - 08:21 AM.

[simonlpearce]

Hmm so the immobiliser is in no way related to the fuel pump then?

[slindborg]

I believe it 'can' shut the pump down, but only after startup. Just as a test, hardwire the pump (via a fuse) to the battery...

[Arno]

Check the inertia switch and the wiring to that... It looks like a big rubber push button and is located in the engine bay at the gearbox side near the boot wall. It will cut the fuel pump power in a crash, but they are known to corrode inside as well, so can fail silently. Sometimes the spade connectors on these corrode too. Bye, Arno.

Edited by Arno, 19 May 2011 - 10:29 AM.

[simonlpearce]

I believe it 'can' shut the pump down, but only after startup.

Just as a test, hardwire the pump (via a fuse) to the battery...

What size fuse? I assume i only need to run a positive to it so could i prime it from a trickle charger which already has a fuse on it?

Check the inertia switch and the wiring to that... It looks like a big rubber push button and is located in the engine bay at the gearbox side near the boot wall.

It will cut the fuel pump power in a crash, but they are known to corrode inside as well, so can fail silently.

Sometimes the spade connectors on these corrode too.

Bye, Arno.

I have pressed the button but i havent looked at any of the connections so will give this a try also.