DSC System Fault no stored codes

[shaunyman]

Hi I recently started the X-type after no use for a couple of weeks. DSC Fault appeared ABS light also on.
Checked with ODB2 reader - no codes stored.
Checked battery (six months old - correct type and size)
Disconnected and charged over night.
DSC fault still present next day.
Drove car on 25 mile round trip - no change.
Checked Fuse F13 5A - no problem.
Borrowed a proper ODB2 device from my retired mechanic friend - still no codes stored.
Checked earth connections - all fine.

Error seems to found during system check. ie it appears a few seconds after switching on ignition but before attempting to start car.
What should I check next? - Any ideas? Many thanks Shaun

[shaunyman]

PS forgot to specify car is 2007 2.0 Diesel Estate

[steve_m]

I had the same thing on mine.
It was the left rear ABS sensor being out of range due to corrosion on the hub moving it somehow.
Took the sensor off and replaced it with a washer put in first, that fixed it.

[Astromorg]

It would be worth checking the brake pedal switches for correct operation. There are two of them - one closes on braking to switch the brake lights on and the other opens to cancel cruise control.
If they don't operate as soon as the pedal starts to be pressed, they may need adjusting. Their operating pins are on a ratchet inside the switch body and can be pulled out to then allow the switches to reset to their correct position when the pedal is next pressed.

[shaunyman]

First apologies for delay in replying. The forum would not allow me to reply to my post, but it appears that James Blackwell has managed to get it sorted for me now - thanks to him.

Firstly Steve_m - Is your x-type the 4wd? Aas far as I know they are the only ones with replaceable/removable rear sensors. The rear sensors on the 2wd appear to be an integral part of the rear hubs and look like they can only be replaced by exchanging the entire hub.

Thanks also to Astromorg - I will definitely take your advice and check the pedal switches - once it stops snowing!

In either of your cases did you not have any ODBII codes set? My understanding is that the generic ODBII codes in the range C0030 to C003C relate the wheel speed sensors and there is a Jaguar specific code P1571 which relate to Pedal position switch malfunction. I have read various claims that not all ODBII readers will show you all the codes set and that AUTOLOGIC or similar may be required, but I would have hoped that the fancy bit of kit I have borrowed would at least show any ODBII generic codes set on an 2007 vehicle.

I will report back on the pedal switches.

Thanks - Shaun

[shaunyman]

Further to the above: I have checked the brake and cruise switches all appear to be fine. The brake lights work as they should, and the cruise control is unaffected!! Took the car for a short drive to verify the cruise engages normally and disengages with a touch of the brake pedal. Now if the cruise is working, what does that tell me about wheel speed sensors. I would think that on a FWD car at the very least the front sensors must be working? As for the rear sensors I can't find a definitive answer for x-type. I have seen claims that some cars (non-jags) require all sensors to work to allow cruise to function, and others require only the driven wheels to be working.

So I am left with fully working cruise, DSC fault and ABS light on, still no ODBII codes.

I studied the fault presentation a little more carefully. When I switch on the ignition all the warning lights are illuminated including the ABS, but the DSC fault is not mentioned. As the system goes though it checks all the lights including the ABS then go out. Half a second later the DSC fault appears and the ABS light relights.

This suggests to me that whatever ABS checking is done at this point is being satisfied, which I guess can only checking electrical connection to the sensors as nothing is moving. Then whatever causes the DSC error to be spotted then makes the ABS light to come back on. Does the DSC use other sensors not used by ABS e.g the YAW sensor, or other sensors I am not aware off? Having checked the net there are a number of ODBII codes for the YAW sensor either not reporting correctly, or an electrical connection issues, but I don't have any of them set.

I need a new straw to clutch at.

Shaun

[steve_m]

Yes, mine was the 4 WD drive and it was quite a while ago so can't remember if there were any codes.
Sorry not to be of more help.

[shaunyman]

No Worries Steve. Thanks for taking the time to respond

[robv12]

sounds very much like a front wheel speed sensor failure to me

[Astromorg]

The problem with fault finding on the DSC system is that the twenty or so relevant codes are all of the format C1xxx. The 1 indicates that the codes are Manufacturer Specific and only Jaguar enabled scanners can pick them up. If neither yours nor your friendly mechanic's scanner have this capability, then there is every chance that a helpful code is lurking in the background waiting to set you on the right path

Can you find out if your mechanics scanner has that feature? If not do you know of any members close to you who might have such a scanner.

If you're in reach of the Southampton/Portsmouth area I'd be glad to do it for you.