and after a quick glance at the beating the dead horse I read this;
Principles of Operation
The Adaptive Damping Control Module (ADCM) uses a
combination of information from other system modules
and data from the accelerometers to measure the vehicle
motion and driver inputs. Using this information, the
module applies algorithms to control the dampers for the
existing driving conditions.
The ADCM receives signals on the high speed CAN bus
from the following system components:
Anti-Lock Braking (ABS) module
– Vehicle speed
– Brake pressure
– Lateral acceleration
– Steering angle sensor signals for steering wheel
speed and angle
Engine Control Module (ECM)
– Brake switch status
– Throttle pedal position
– Engine speed
– Engine running status
Transmission Control Module (TCM)
– Gear position


With the vehicle in motion, the ADCM monitors the
input signals and operates the damper solenoids appro-
priately. The input signals are compared against algo-
rithms within the ADCM and preset speed thresholds.
The gear position signal is also used to determine lon-
gitudinal detection and, along with the speed signal, is
compared against algorithms to select the appropriate 'soft' or 'firm' damper setting.

 

Yes, as in "what gear is currently selected". This does not involve the S button.
Your welcome.

 

thanks except, my 2008 does not have an S button, rather a selector that moves to the left as in S. I was and have been referring to my 2008 XK and tried to make that very clear.Gear selector position not gear selected (as in paddle shifting). Grab the selector and pull it to the left, as in “position’.



This is getting old, I’m correct. Good bye.

wj

 

@wymjym First understand I’m not dismissing your perceptions of your car and I’ve not driven your car, but I also ordered a new emerald fire XK convertible in 2008 and quite familiar with how it operated and I’ve been working on Jags and Rovers for over 20 years. There’s no difference in operation whether the R version or not. The Jaguar documentation for the transmission also refers to the difference between “D” and “S” and makes no mention of the adaptive dampers. Again for the 2007-2009, “S” only changes the shifting characteristics and nothing more.

This isn’t the first time this topic has been brought to these forums as many have believed the “S” transmission map also affects handling, exhaust, performance, etc. Jaguar was not that sophisticated at that time.

 

Quote:

Originally Posted by jahummer

@wymjym First understand I’m not dismissing your perceptions of your car and I’ve not driven your car, but I also ordered a new emerald fire XK convertible in 2008 and quite familiar with how it operated and I’ve been working on Jags and Rovers for over 20 years. There’s no difference in operation whether the R version or not. The Jaguar documentation for the transmission also refers to the difference between “D” and “S” and makes no mention of the adaptive dampers. Again for the 2007-2009, “S” only changes the shifting characteristics and nothing more.

This isn’t the first time this topic has been brought to these forums as many have believed the “S” transmission map also affects handling, exhaust, performance, etc. Jaguar was not that sophisticated at that time.

Not knowing for sure..., Just because a shifter description does not make mention of adaptive dampers does not necessarily convince me that there cannot be some algorithms coming out of the transmission module going to the Adaptive module for input into the shocks. What I feel is significant at high speeds of 90 plus on bouncy highways. I would have to guess in the order of 50% additional dampening.

So according to what you wrote, are you saying that using the S selection does not even effect the exhaust valves?

We are all here trying to figure out things and have a discussion. Sure would be nice to be able to do so without a bunch childish ego innuendo statements unnecessarily floating about.(Not meaning you JA!)

 

@kenbowen exhaust valves are tied to engine RPM and vehicle speed. There’s a chart somewhere which shows the valve tune tables. For 2007-2009 Dampers are tied to vehicle speed ( plus the inputs listed in the manual) and only have 2 modes, soft and firm.

@wymjym “D” and “S” aren’t transmission gears, they’re actually PCM maps. The manuals reference to gears is quite literal, gears in the transmission - 1 through 6….

 

[QUOTE=jahummer;2737465]@kenbowen exhaust valves are tied to engine RPM and vehicle speed. There’s a chart somewhere which shows the valve tune tables. For 2007-2009 Dampers are tied to vehicle speed ( plus the inputs listed in the manual) and only have 2 modes, soft and firm.

I was referring to the exhaust pipe(muffler box) valve opening and closing based upon the shifter being placed in either D rive or S port mode and not engine valve timing.

 

As was I. See pic of the table showing what I was referring to.

 

That really didn't solve anything though;

 

Not sure if mine has a soft setting. it's pretty hard around town - I may connect up my cheap sillyscope tomorrow and check that 400 HurtZ signal and see what happens when I move from Drive to Sporty mode.

 

remember that you must be moving for the shocks to switch!
Jahummer, Indulge me and read the pdf that Guy linked to. It is focused on the cats system and goes into detail which is not mentioned elsewhere. Specific wording....I never said nor meant to imply a gear selection, I said gear Selector as in shifter. I"ve reread that pdf and have zero doubt of my interpretation.
also I reached out to moscowleaper...he replied that when in S mode the steering rack and (if fitted) the
cat shocks are affected.
wj

 

I'm happy to know if I've been provided incorrect information and learn something! I'm quite familiar with the documentation, I've had it a long time. GEAR POSITION isn't the same as transmission operating mode. The manual refers to "D" and "S" as transmission operating modes. I will say the PDF you reference's quite vague and certainly could be open to any sort of interpretation the reader may wish.

EDIT: and the PDF does NOT say gear selector or shifter...

 

Correct it says gear position signal
I read that as the position of the 'selector or shifter'...maybe my bad but since I can't see how gear position signal could literally be the position of a gear...I made an interpretation of that. No matter what, my 2008 XK does exhibit different driving characteristics which could only be influenced by the shocks.
Also, I asked MoscowLeaper about this since he has an ecu tune for the hp26, I believe he should have the knowledge, he confirmed there is an input based on either "D" or "S" (apply the nomenclature you like to describe these two selections).
as to why you and many others never sensed this very obvious (to me) change, possibly the fact that my shocks are worn out and soft as in super soft. I assume that soft on a new set wouldn't be nearly as soft and the differences between new soft and hard is less dramatic that worn out shocks going from soft to hard (I'm just spitballing here, a guess).
Too much minutia is at play. Thanks for your patience and civility.
wj

 

Sillyscope not gonna happen - tried pushing resistor leads down past the wires on the plug - no connection - that is one weird connector - don't want to strip back the insulation on the wiring.

 

It does make sense that in sport mode the suspension would go to hard - will have to try it out next time I'm out for a drive - we got plenty of bumps around here.

 

4.2 NA (and I think 4.2 R) have a two stage damping system: firmer and softer, or if you want, hard and not hard, or maybe tumescent and flaccid? Dunno....

The 5.0 CATS are fully variable between the firmest and the softest setting.

 

JA, thanks for posting this chart. Can you tell me where it came from? I would like to do some further reading as I had always surmised that the exhaust valves were controlled by the gear selector being placed into Sport mode... So I guess by pulling the infamous fuse out you will just defeat the table whether it be in D or S?

 

The chart comes from the service manual. In my copy it’s on page 2341 (of 4000) of the 4.2 manual.
Pull the fuse, the valves are permanently open.

 

Many thanks, beat me to it!