2000 3.0 Stype. Should the sport mode switch light up or show in the gauge cluster? I am never sure what mode I am in as nothing lights up

 

FWIW, I was expecting a sport mode indicator on the dash as well Alas, mine has only an orange indicator light on the switch itself

Cheers
DD

 

Better than what I have which is zero

 

On my '02 V6, the only indication is the little red light above the S on the switch. No message nor symbol on the dash, unfortunately.

The switch is only momentary action, too. It doesn't latch into a raised or recessed position.

 

On my 01 V6, nothing on the dash but a light on the S switch. Unlike Karl's though, mine stays on all the time. I leave it depressed and unless I press it again, it stays on.

 

I think Karl meant the switch doesn't physically (mechanically) latch down.

If the light doesn't come on, faulty light or switch. You should be able to figure if the switch is OK by the effect (or not) on the gearing / gear changes.

 

Yes, that is probably a better way to describe the switch operation. You certainly don't have to hold the switch to be in sport mode. When you push the button, you never feel a click like with a typical switch. Nor does it latch in a recessed position.

If in normal mode, push and release the button. The button springs back up, and the light comes on and stays on. The transmission is now in sport mode. It stays that way until selected off, even for subsequent drive cycles.

To return to normal mode, push and release the button again. The button springs back up (same as before) and the light turns off.

I have no idea if the switch contacts are physically latched in an open or closed position, even though you can't feel it. I suspect it is merely momentary action, a signal to the controller to switch modes, but that is only a guess. In other words, the light is probably feedback for the controller mode (normal or sport) and not necessarily the switch position.

Have you tried testing the light at night? Maybe the LED is barely working and is very dim. Try parking in a dark location and play with the switch. Maybe you will see a faint glow.

 

Bueno and thanks for that

 

Further clarification . . . switch action is neither a 'normal' double throw where the switch position indicates 'on' or 'off' state, but nor is it momentary which dictates that the switch position and any circuit(s) controlled by it, always return to 'off' whenever your finger releases button. This sport mode switch is correctly known as a 'push on / push off' action which toggles between 'on' and 'off' with each button press. As both John and Karl point out, the internal LED should indicate circuit activation with each button press, despite the switch button returning when you release it.

Hence the need for the LED indicator. If the LED is not toggling 'on', check fuses (always Rule #1)

Cheers,

 

Actually, that might be Rule #2.

For Rule #1, maybe check the wiring diagrams to see if the circuit even has a dedicated fuse...

I was wondering about the fuse myself, so take a look at figure 04.1 in the wiring diagrams:

JagRepair.com - Jaguar Repair Information Resource

Surprisingly, the switch is wired as an offshoot of the General Electronic Control Module (GECM). The switch contacts (on/off request) are shown as an input to the GECM. The GECM apparently sends the request to the Powertrain Control Module (PCM) via the Standard Corporate Protocol (SCP) bus.

The LED (within the switch) is an output from the GECM, probably originating from the PCM. Note how there is no specific fuse protection in the LED indication circuit. The fuse protection probably comes through one of the fuses feeding the GECM. I'm not sure how many fuses the GECM has, but I see at least two in figure 07.1. If a fuse were to open feeding the GECM, I think you'd see multiple failures on different systems. If the Sport Mode LED is the only thing not working, I doubt a fuse is the problem.

My hunch is an LED draws such low power, the engineers didn't worry too much about overcurrent protection for it. Just another hunch, but the GECM may have some current limiting function, too.