This is probably a derpy question, and most of you would probably tell me to RTFM, but I don't have a user manual right now...can someone tell me what that LIM button actually does? I can't figure it out for the life of me.

 

It's probably the Automatic Speed Limiter button.
Mine has ASL on it not LIM so I'm guessing later models (mine is MY 2015) changed it from ASL to LIM.
My Owner's Handbook says:

1. ASL on/off: The ASL button switches
between Cruise control and ASL. The
systems cannot be used simultaneously.
The ASL warning lamp will illuminate when
ASL is active. See 40, AUTOMATIC SPEED
LIMITER (AMBER).
Note: ASL only operates at speeds between
30 km/h (18 mph) and 240 km/h (150
mph). However, the speed limit can be set
while the vehicle is stationary.
2. Set/increase the speed limit: The set speed
limit will be displayed in the Message
centre.
When a speed has been set, the engine will
respond normally up to the set speed.
Further accelerator pressure will not
increase the speed beyond the set speed,
unless sudden, rapid acceleration
(kickdown) is applied. If kickdown is
initiated, ASL will be suspended.
3. Resume ASL assistance: ASL will only
resume if the vehicle's speed is less than
the set speed and greater than 30 km/h (18
mph). If these criteria are not met, a
message will be displayed in the Message
centre.
4. Decrease the speed limit: The set speed
limit will be displayed in the Message
centre.
5. Suspend ASL assistance: ASL can also be
suspended by applying sudden, rapid
acceleration (kickdown).

It is not a button or function I have ever used and I never will use it.

 

I had it on my XKR and found it great fun to floor it [edit: without engaging kickdown] from the lights knowing I wouldn't exceed the speed limit. Not highly useful apart from that, though, IMO.

 

What the heck...what purpose does it serve, actually? It just sets an artificial limit...but I mean, why? Can't say I've seen that in a car before. I don't quite get it.

 

Well, if you can't control your right foot it could be useful if law enforcement is being mean in certain places. That said, I've never had a need to use it in my F-Type.

 

The LIM works in conjunction with the front mounted camera to detect speed limit signs. If LIM is activated then you will be limited to the identified speed. There are settings for allowing a percentage speed above it (I think 10% max). Kicking down accelerator will override the lim setting for overtaking etc.

 

Mine (MY18) doesn't have a front mounted camera, but it does have LIM. My manual states that the set speed is the top limit, no mention of adjusting it via speed limit signs. I'm not even convinced that cruise control responds to speed limit signs, maybe latest models are different?

 

I have never heard that any MY years respond to actual speed limits, just the limit set by the driver with the LIM (ASL) function. Comes in handy when you’re in the twisties and perhaps enjoying yourself too much when coming out of the corners. It takes less than a second or two to be 30+mph over the speed limit. Back woods smokies aren’t appreciative of such feats.

 

When I bought my first Jag, I thought LIM was the dumbest feature I would never use. Now, if I were to switch brands, it’s a feature I would miss. Especially in the automatic (XF), I have a hard time just not pushing the pedal, even when I know better. I recently didn’t use it and had to pay driving tax for passing a slow poke in a known speed trap area. Was only 2 seconds, but the Jag doesn’t need long and it was enough to cost me.

ASL is better and safer than cruise as I maintain full control of vehicle speed while keeping myself out of trouble.

 

Maybe just a UK feature then as my MY19 identifies the speed limit via the front camera and if LIM is active will limit speed as described above.

 

Might also be a feature of the US MY20 cars as well. Anyone on the forum have an MY20?