Jaguar Forum banner
21 - 40 of 80 Posts

·
Super Moderator
Joined
·
20,513 Posts
I get DCS not available, Emergency Brake Assistant not available, Park Brake Fault and cruise not available all pop up when I try to do anything too quickly with the gear box. I.e. reverse back, then flick into D and try to get going all in a hurry. I miss a manual gearbox!!

Sent from my HTC 10 using Tapatalk
Brake pedal switch is the likely culprit.
 

·
Registered
Joined
·
1 Posts
I Had this fault on my 3rd XF. just bought my third XF an XFS 3.0TTD 2010. first thing i do is remove all the brakes shot blast and paint them and reassemble, completed this in a few days. i couldn't''t get ant brake pressure after the rebuild, this happened before and it was a faulty master cylinder, so i replaced the master cylinder, no change so i then changed the booster, still no change. cut long story short it turns out i had to pump the brake pedal whilst using the pressure bleeder. once my brakes where bleed i discovered the brake pedal was too low so the brake lights where always on. For the life of me i could not figure out why, servo was snug up to the firewall and i hadn't touched the brake pedal, suffice to say i never found the issue i simply made a 7mm spacer and all seemed well. On the first test drive after pulling out of the drive my dashboard lit up like a Christmas tree DCS not available, gearbox fault, park brake fault and the cruise was unavailable. no idea what was going on. the car listed loads of fault codes:
P0571:68
P0504:62
U0401:68
U0415:92
P0571:68
P0504:62
P1571:64
U0401:00
Most of the codes said i'm getting gobldigoock from my systems. Being a new car i had just reset the adaptive gearbox to learn my driving style, i thought this had fried the car, i reset the code several times and removed the battery and gave it a 48 hour charge, the battery was new so i new it had a good power source. a day later i was head scratching behind the car, alas i notice the brake lights where on. now knowing how bizarre Jags can be i thought maybe the car is upset about having the brake switch on 247. i cleared all the codes and drove the car with my foot under the brake pedal to lift it to it's highest position(not recommended kids!) the car ran perfectly no errors at all. I turned around to head home, this time i let the brake pedal rest at it's normal position, within a minute all the errors appeared. bingo i had it!, i replaced the 7mm spacer with an 8.5mm to make sure the brake pedal was firm against the end stop, so far no problems. seems all the fuss was caused by the brake switch being activated too long!. what the hell Jag, so if you ride the brake your going to need a costly trip to Jag! So if you have these faults first place i would look is your brake pedal switch. I use Auto engunity OBD software, this not only reads codes but you can also view live data from the car, this proved to be invaluable as i could view the brake switch position and the pressure applied to the braking system not to mention the fault codes. Hopefully this helps someone along the line, i have removed and refitted every part of an XF's braking system so if anybody has any questions please get in touch i would be happy to help. I have Had 3 XF's now and my dad has an XKR, i'm pretty savy on both inside and out any questions please let me know.
 

·
Administrator
Joined
·
29,868 Posts
Welcome Danny. Your hard-won experience seems to underline what D3GGY said in the post before yours.

We have seen a few instances of faulty brake light switch assemblies (there's a lot more than one switch in there) causing issues like this.

Oh, and welcome to the forum, hope you stick around, your practical knowledge is invaluable.
 

·
Registered
Joined
·
27 Posts
Hi guys i have a jaguar xf 2011 2.2d. park brake fault used to pop up on a cold morning but it used to go away immediately but then it decided to just stay there and then later on one day all of the faults came up but epb was working perfectly fine
Emergency park assist unavailable
Park brake fault
DSC fault
i thought it was battery so took it to local garage and got it checked it was giving perfect voltage but still i charged both batteries and then a new error came up

Cannot apply park brake
i tried all of the steps to recalibrate by pressing brake 5 times and then epb but it never works.
took it local garage again, checked with obd reader and there were various codes he asked me to get brake light switch to get changed which i did but still no luck
any ideas please
 

·
Registered
🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
Joined
·
11,940 Posts
Try opening the car and open and close a door. Open boot , wait 10 minutes then disconnect your negative battery lead, wait 5mins then reconnect it cleanly I.e put the clamp quickly and confidently on to the battery post , you don’t want it to crackle a lot, if it does remove for 5mins and repeat
 

·
Registered
Joined
·
27 Posts
Try opening the car and open and close a door. Open boot , wait 10 minutes then disconnect your negative battery lead, wait 5mins then reconnect it cleanly I.e put the clamp quickly and confidently on to the battery post , you don’t want it to crackle a lot, if it does remove for 5mins and repeat
Thanks for your help but tried it many times still no luck, just got battery health checked and it says good charge but it’s 10 year old battery so not sure if it still needs replacement despite it being okay.
 

·
Registered
🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
Joined
·
11,940 Posts
Hmm 10 years is a lot for a battery, I’d be questioning the test. You can get a decent battery for around £130
 
  • Like
Reactions: FCS

·
Registered
Joined
·
1,001 Posts
I would go with Gav above. You said the battery voltage was OK. But there is more to it than that. When a varying load is applied from the electronics it may drop slightly which the electronics will detect. You don't have a lot to loose, as if not due a swap yet, it will be soon.
 

·
Registered
Joined
·
27 Posts
I would go with Gav above. You said the battery voltage was OK. But there is more to it than that. When a varying load is applied from the electronics it may drop slightly which the electronics will detect. You don't have a lot to loose, as if not due a swap yet, it will be soon.
just got it checked from other local dealer and he said parking brake motor is gone and even the parking brake light switch which i changed earlier but he is saying it needs a genuine one from dealer. he gave me a quote of £550. i really doubt it’s a motor because parking brake was qorking perfectly fine it was just the faults on dash that was annoying me but since i took battery out and charged it since then the hand brake stopped working
 

·
Registered
Joined
·
1,001 Posts
Why am I not convinced. If it is the motor it has either sized solid which will have blown a fuse, its gearbox bust which you would hear a werring sound or gone o/c which would be checked easily with a test meter.
 

·
Registered
Joined
·
27 Posts
Why am I not convinced. If it is the motor it has either sized solid which will have blown a fuse, its gearbox bust which you would hear a werring sound or gone o/c which would be checked easily with a test meter.
Thanks again, any idea which fuse to check and gearbox bust? is it a problem with gearbox? sorry am not good with technical language
 

·
Registered
Joined
·
27 Posts
Why am I not convinced. If it is the motor it has either sized solid which will have blown a fuse, its gearbox bust which you would hear a werring sound or gone o/c which would be checked easily with a test meter.
the other thing is that eco start stop fault is there aswell and even cruise control isn’t working so i still think it’s some electrical issue.
 

·
Registered
Joined
·
1,001 Posts
I meant the gearbox on the EPB motor.
You really are describing a battery issue. I would go for a new battery. Another possibility is the CJB but I would hope not but just in case have a look at the plug which gets the water issue find it on the forum there is lots of stuff on it.
 

·
Registered
Joined
·
27 Posts
went to halfords and grabbed AGM battery for £186. Fixed all the problems and hand brake started working perfectly fine now. the new AGM battery is compatible with start stop function. not sure if i need to change the smaller. ( auxiliary) battery aswell?
 

·
Registered
Joined
·
2,805 Posts
Another multiple electrical faults fixed by replacing the main battery. I'd like the know how the dealer came up with the diagnosis of a failed EPB motor and the brake light switch. Another case for ignore the dealer, they have no clue. Only here to fleece us and cause us misery. It's rare for a battery to survive to 10 years, you did well with that one. I can't assist with the aux battery, none of my cars have one.
 
  • Like
Reactions: FCS

·
Registered
Joined
·
4,483 Posts
I'm fairly sure I've read elsewhere that the BMS manages re-charging of both batteries when it is running, main one first then secondary if needed.
 

·
Registered
🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
Joined
·
11,940 Posts
went to halfords and grabbed AGM battery for £186. Fixed all the problems and hand brake started working perfectly fine now. the new AGM battery is compatible with start stop function. not sure if i need to change the smaller. ( auxiliary) battery aswell?
You’re welcome 😉
 
  • Like
Reactions: FCS

·
Registered
Joined
·
1,001 Posts
Glad you have it sorted, not a bad forum is it. Might not be a bad idea to change the small battery but it is not as important, do it at your leisure.
 

·
Registered
Joined
·
27 Posts
Another multiple electrical faults fixed by replacing the main battery. I'd like the know how the dealer came up with the diagnosis of a failed EPB motor and the brake light switch. Another case for ignore the dealer, they have no clue. Only here to fleece us and cause us misery. It's rare for a battery to survive to 10 years, you did well with that one. I can't assist with the aux battery, none of my cars have one.
Glad you have it sorted, not a bad forum is it. Might not be a bad idea to change the small battery but it is not as important, do it at your leisure.
Bad news! just started my car in morning and it took a bit of hesitation to start with ♾️ symbol on dash and then all the faulty came up again. luckily the handbrake is working perfectly fine. i’m not sure if it’s the other small battery that’s doing this or it’s the alternator.
 

·
Registered
Joined
·
2,805 Posts
Was the BMS module reset when the battery was replaced? If you have a multimeter, you can check the voltage across the battery prior to starting then once started to check, in simple terms, if the alternator is providing any output. The charge current from the alternator is controlled by the BMS module so the output will vary as it charges and discharges the battery under normal operation. There's a few threads to have a read through as a few have had battery/alternator issues recently.
 
21 - 40 of 80 Posts
Top