Wiring a hidden power isolating switch

Hi all, I realise this has been discussed a zillion times before and from what I can make out often basic but mixed messages depending on exactly how the question is asked...... Incidentally this is for a TD5 90, 2001.

Here's what I want to achieve. I want to fit a hidden switch (not the cheapo fleabay one with the red handle) in the cab, I want it to basically stop the engine from being started if the switch is'nt made. I don't "really" want the ignition switch being used as I believe this can easily be bypassed. I do not need this to be an engine "cut off switch".

I have limited electrics knowledge but can find my way around and trying to learn all the time, I have had one suggestion of fitting the switch on the fuel pump solenoid as this way I keep power to the vehicle for radio etc. Another suggestion I had was to fit the switch as a battery isolator but with a fuzed bypass to keep radio power going.

I'd be really pleased if anyone can support or trash either of these ideas or come up with a relatively simple alternative idea for me. (in kiddy language....) . If anyone could send a link for a schematic of how to do this or even show a basic sketch that would be brilliant. - Thanks in advance for any help.

download the Rave for your motor. squirkit diags are in there.

The Mad Hat Man said:

download the Rave for your motor. squirkit diags are in there.

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Thanks Mad Hat Man, I found the workshop manual and loads of other stuff but cant find the RAVE for the Defender TD5 1997 -2001, I can find just about any other variant but not this!

The Mad Hat Man said:

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Thanks very much, I’ll check it out tomorrow on my computer, it’s not so easy on the phone!

Is there a website or link that you’d recommend for these pdf documents as I don’t seem to have much luck with what I put into Google?

The Mad Hat Man said:

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Thanks buddy, got it now and read the fuel system section completely. What this has shown me (unless I'm misunderstanding what Ive been advised) is that the advice for connecting the switch into the fuel pump solenoid is for a different engine and not the TD5 Defender as this doesnt have a fuel pump other than the one in the fuel tank and so no solenoid attached!!! Move on to the next idea please guys.....

"not the cheapo fleabay one with the red handle"

Most of the time these are not just an engine isolator but instead a battery isolator incorporating engine shut-off and alternator protection, the idea being (apart from a simple layer of security) is that in the even of an emergency you hit one switch and the battery is made safe and the engine shuts down in one easy action (FIA type only).
I have fitted one to each of my LR's over the past 30+ years plus also to older cars like my wife's old MGB.