DSC

[owlgrr]

Sometimes on start up an amber display shows 'DSC NOT AVAILABLE' a and stays on until a restart

[Old Peter]

I got that once, Brian, and it occurred a few times for a day or two.  I concluded that when the message came up for the first time it was due to my wife pressing the button when she was looking for the heated seat button.

 

You can remove the message with an OBD2 code scanner.

 

Peter. 

[Raistlin]

Was this sorted out Brian?

[jaydeeuu]

On 06/02/2015 at 11:16 AM, owlgrr said:

Sometimes on start up an amber display shows 'DSC NOT AVAILABLE' a and stays on until a restart

Yeah .... Also get that most days, apparently (maybe) my local garage tells me the rear pads could do with being replaced? - However, spotted in a much earlier post that if you depress the brake pedal on starting, the warning doesn't appear, the comment is quite correct - which is what I do !!!.

At my next service I will have a diagnostic to query why.

John

[Raistlin]

41 minutes ago, jaydeeuu said:

Yeah .... Also get that most days, apparently (maybe) my local garage tells me the rear pads could do with being replaced? - However, spotted in a much earlier post that if you depress the brake pedal on starting, the warning doesn't appear, the comment is quite correct - which is what I do !!!.

At my next service I will have a diagnostic to query why.

John

John,

Your problem is almost certainly a faulty brake pedal travel sensor. This is located in the brake servo. We have tried to replace the item but it proved beyond the capabilities of a moderately well equipped workshop and a replacement servo cured the problem. If you look at your servo you should see two electrical connectors on the front face, either side of the master cylinder mounting. The other electrical connector is also involved in the DSC function although its name escapes me at the moment.

In later cars (2006 MY), a completely different servo was used and the DSC function was wholly contained within the electronics of the car, obviating the need for the servo mounted sensors.

[jaydeeuu]

12 hours ago, Raistlin said:

John,

Your problem is almost certainly a faulty brake pedal travel sensor. This is located in the brake servo. We have tried to replace the item but it proved beyond the capabilities of a moderately well equipped workshop and a replacement servo cured the problem. If you look at your servo you should see two electrical connectors on the front face, either side of the master cylinder mounting. The other electrical connector is also involved in the DSC function although its name escapes me at the moment.

In later cars (2006 MY), a completely different servo was used and the DSC function was wholly contained within the electronics of the car, obviating the need for the servo mounted sensors.

Hi Paul .... Many thanks for the response, I will pass your views on when I get the Jag serviced - as a further puzzle with the brake pedal.

Before starting the car and with my foot on the pedal, the pedal is hard; as soon as started the pedal becomes quite soft and appears to have a fair bit of movement. This is something I have not experienced in other cars I have owned/used, and the basis for the rear pad comment from my local garage.

John

[Raistlin]

John, the vacuum in the servo decays over time unless it is replenished by the engine and or vacuum pump. That is why the pedal feels hard. Once the vaccum takes effect the pedal will appear softer as it now has servo asistance. It may also seem to sink a little, but not to the floor of course.

Clearly, without trying it myself I can't make an objective judgement but from what you've said, providing you are confident with the braking abilities of the car, there is unlikely to be anything wrong with the brakes / servo.

If, on the other hand, the pedal goes hard after continued brake application then there is a vacuum fault, either with the servo or the vacuum pump. The servo on the S-Type is notorious for this. In fact, my own car has eaten two servos in 18 months.