I am very sorry to have stepped into your sandbox.

I did not say this was applicable to the S type. In my post I pointed our that the XJS did have a kick-down switch. This switch acts in much the same way as the OP posted that his tech described. I simply pointed out that some Jaguars do have such a switch and asked if perhaps his tech had made a simple mistake.

 

I misread your post also and understood "We do have what is called a "Kick-down switch" to mean 'we S-typers' and not 'you XJSers'.

It's clear now.

Eats shoots and leaves.

 

You might get 10 whp with high-flow cats along with a full exhaust system, but that's about it.

 

Alpine Jaguar...I used to service my car there back when it was under Select Edition and all I could say is that I loved the XF service loaners...haha

From experience though, their service department was pretty flexible with me price wise. I recall that they cut and programmed my key free of charge one time. Depends on which service advisor you get....

 

There's no physical kickdown switch on the S Type, there's no need for one.

On a car with a cable throttle the switch is used to get the transmission downshifting without waiting for the load on the transmission to demand it. This is often called passing gear.

The S Type (and other drive by wire cars) use a sensor on the accelerator pedal to measure its position. When this is reading 100% the car goes into WOT (wide open throttle) mode. It stops listening to what the O2 sensors are telling it and moves into open loop mode, the transmission also behave as if it were in sport mode and will hold gears until later in the rev range (I've not investigated whether sport mode holds them longer still).

Now, it can feel as if there is a switch in your pedal. If you press it down gently with your foot you will find it comes to a natural rest, if you give it another poke it will finish its travel. I believe this may be for those used to an actual kickdown switch being present