Thread: CVD recalibration

Recalibration was certainly done, actually over-done for normal back-roads as the shocks were too stiff for normal road use but great on my very rough driveway with +30mm in use where bounce was very appropriately controlled. Calibration mode was then re-initiated on the blacktop with the new ride very reminiscent of how it was when first purchased, although now a little soft again on those big driveway pot-holes. Setting calibration mode on the road-side took about 60 seconds.

Similar to a post on a Jag forum regarding a MY10 Jag with adaptive dynamics, switching off DSC makes the ride very firm and induces slight over-steer tendencies on fast bends with the tyres pressure that I use. Switching DSC back on causes an immediate relaxation of the damping allowing the vehicle to glide over bumps and ripples.

DSC on my vehicle cannot be off with ACC in use. If DSC was off then it is set back on and DSC cannot be set off with ACC in use.

With the shocks feeling very tired on smaller bumps and patched-up bitumen roads at 93K kms, I've been thinking its time to replace them so gave re-calibration another try. Switching DSC off still produced too firm a ride so there was still life in the shocks. The good ride has again been restored, for the moment anyway. This time the 10 second calibration was done at 80 kph on a nearby partly sunken and patched section of bitumen.

would this be the same on MY10 Graeme?

MY10 CVDs are the same, but not all MY10 were fitted with CVDs.
A disadvantage of recalibrating is that there is no default to return to if the road surface being used doesn't replicate that used to set them initially, resulting in inappropriate calibrations and possibly several attempts to get the shocks working as desired.

Hi Graeme, Which IIDTool software version are you using? I would like to re-calibrate my L494 CVDs as I think they are too firm, It might be interseting to play with the calibration and try and soften things a bit.

I select Calibration from the main menu then select active dampers.

I accidentally found that calibrating while not moving resulted in excessively soft damping and calibrating on severe ruts and bumps resulted in very good damping on the severe ruts and bumps but generally excessively firm damping, so finding an appropriate surface is necessary. After having driven to town and back since the last calibration I consider the ride restored to the original smooth but controlled.

L405 owners often look for a firmer ride but I'm not surprised that the L494 is firmer. Switching off DSC firms the shocks so you might want to get a good feel for that ride before you re-calibrate as another yardstick and as a check that you're not confusing inadequate damping on short suspension movements feeling like over-damping.

The updater s/w shows that the tool is running Beta version B2624 but that B2643 (release) and 3 custom versions are available including B2644 which IIRC was to provide ACC calibration and the others a specific ecu firmware upgrade and an option to calibrate the RDCU on the L322.

Originally Posted by Graeme

I select Calibration from the main menu then select active dampers.

I accidentally found that calibrating while not moving resulted in excessively soft damping and calibrating on severe ruts and bumps resulted in very good damping on the severe ruts and bumps but generally excessively firm damping, so finding an appropriate surface is necessary. After having driven to town and back since the last calibration I consider the ride restored to the original smooth but controlled.

L405 owners often look for a firmer ride but I'm not surprised that the L494 is firmer. Switching off DSC firms the shocks so you might want to get a good feel for that ride before you re-calibrate as another yardstick and as a check that you're not confusing inadequate damping on short suspension movements feeling like over-damping.

The updater s/w shows that the tool is running Beta version B2624 but that B2643 (release) and 3 custom versions are available including B2644 which IIRC was to provide ACC calibration and the others a specific ecu firmware upgrade and an option to calibrate the RDCU on the L322.

Thank you. On my current version I can't select active dampers under calibration. I'll ask GAP if I can get the beta version you have.

I need to study the suspension further as it may be a case of inadequate damping feeling like over-damping as you say. My car has 90K on it but it has pretty much all been city driving.

Probably better to ask for a version that supports L494 CVD re-calibration.