Hi all , I am wondering if any Jaguar techs out there can help me with a rather frustrating issue that I have had with a S type recently. quick Overview , I work in the motor trade and mainly work on and run Diesel Pugs volkswagens citroen , my fleet covers high mileage and i would consider myself a competent mechanic who has a good track record. That track record has taken somewhat of a bashing recently when I was asked , By my Mothers partner to change the front brake pads and look at adjusting the handbrake on his 2001 s type 4 ltr V8.
Ok so I changed the pads on the front which were very worn / slowly retracted the pistons / refitted the pads job done , next I stripped the centre console to adjust the handbrake , only to discover that there was no manual adjustment. now i undertook one thing that i believe may have caused the issue , in order to remove the centre console fully so that i could gain full access to the handbrake lever i had to disconnect the dsc switch and sport switch , which i did with the ignition off but battery connected. so realizing that the handbrake was a self adjusting mech i re assembled the centre console and then ( the second procedure which i thought may have caused this issue) I slowly and gently pumped up the brake pedal to settle the pistons on the pads.

so on with the ignition and bang DSC fault , ok i thought no worries , its just because i removed the dsc connector from the switch.
so i scanned the module and got C1286 mechanical booster failure. tried to clear kept coming back, damn!!

so i took the car to a mate who is an ex jag tech , he took it to jag they brought it back to me and said it needs a servo unit ( Americans call it booster / jag said that they collapse internally) then it will need clearing down again. well i obtained a servo from jag specialist breakers / fitted it and light was still on , so i took it to another mechanic mate who let me use his snap on scan tool ,I traced the code, tried to clear and it came straight back on!! double damn!!

so im stuck , my gut feeling is i have inadvertently spiked the control module / abs unit by removing the switch for the dsc and not as i originally thought , broken the sensor by pumping the brake pedal.

car drives fine and traction control works with accompanying flashing dsc light when slippage detected / abs works fuses are all ok

can any one help or shed some light , I have trawled the internet for a test / pin data procedure but to no avail. any pointers would be fantastic!!

thanks

Kris

 

Hope for a tech to answer but I can say that the jag codes PDF shows that recalibration (of the module) will be needed so clearing isn't going to work. Looks like you "should" have a flashing MIL to show recal is needed,

It mentions that one potential cause is brake pedal related but I don't see how that helps (sorry).

Er... congrats on today's unique-to-me-fault

 

Thanks for the reply and confirmation of "unique-to-me-fault " thats one accolade i would happily do without :-)

so your pdf states that re calibration is required for booster / servo replacement ( not module as this is still original ) i.e setting the servo pressure sensor in with dsc module brake switch etc. I dont have any mil light on and there are no faults stored within the pcm. set up is only available at jag i take it ?? and what do you think caused this issue in the first place / out of interest, thanks again

 

I don't know. The PDF is in JTIS which is on here, PCM codes are irrelevant for this.