This has to be one of the dumbest ideas in the history of British auto making ELECTRIC park brake ???!!! Sure let's overcomplicate a simple necessity ! Anyway...here's the question. Brand new battery. Reset per Jag tsb and "apply foot and park brake" warning went away immediately. 3 days later it's back. Didn't use it and it also didn't set itself when put in park those 3 days either. But Sunday I put it in park and there it is. Won't release. Disconnected control module and reset again. Freed park brake but still have the same warning and beeper. No low voltage warning lights. Have tried same tsb reset procedure and still have light and the brake sets and won't release about half the time. I hear it making a machine gun Ike sound when it engages. Not normal sounds. Bad EPB module ??? If it had a brake handle like a normal car...even an XJS handbrake lever would be better !!!

 

As far as I know, there is no such critter, unfortunately. The voltage can drop way down and you won't get any warning. Meanwhile, certain systems start to act up, and the EPB seems to be one of the most sensitive to low voltage.

You may find this thread of interest:


https://www.jaguarforums.com/forum/s...attery-193787/


Specifically, I would make sure your battery is staying fully charged while driving. Could be the charging system is not up to snuff, and even that brand new battery will slowly run down and cause an EPB problem.

For troubleshooting, some people have hooked up a battery charger each night for a week or so. If the EPB then behaves each day, you know low voltage was the root cause and you can troubleshoot that instead of the EPB system.

Please report back with what you find, so we can add your results to the scorecard.

 

Yea I'm about to head to our shop an put load it after on it and check the alternator output now...it's a good thing I love this car as I do...lol

 

OK folks. I had exactly the same problem on my newest in the camp 2002 STR. Could disregard it for a short while if i cleared the fault with the code reader and not worry about it after that if i pushed down on the EPB button whilst turning off the ignition. all good but only a short term fix! .or until i forgot! .....so this last weekend i set about discovery of source and fix the issue....this may work for you!

I have had several issues with what i call dry/poor connections/ joints on my other Jags that have caused all sorts of problems with everything from door mirrors looking skywards upon car unlocking to many more silly issues!!!!! and are not a flat failing battery!

sooo....I pulled back the cover in Boot/trunk (right hand drive in uk) to expose the the electronic control module and the EPB module (are both next to each other) i both disconnected and reconnected them both...and with a good helping of electrical contact clener...let em dry out. You will understand that this was another trial ....but

Hey presto yippee do do the codes and all read and cleared and all done....no more EPB issues...what a relief!

hope that helps

 

Battery appears to be weak... alternator output is good. OK looks like I may have to pony up for a Varta after all...interstate batteries have done well in every other car for me but I guess not for this Jag...

 

Thanks so much for the update. We have so many unresolved threads here. It can very frustrating when we are just trying to help and the original poster never follows up, so you have our thanks. Can't wait to hear the final outcome if a new battery resolves the issue.

Can I pick your brain about how you determined the battery was weak? What type of tester was used? I'd like to update the scorecard thread with details of the best type of battery tester to use.

Here's what I have:

1) A vintage Schumacher BT-100 resistive load tester, aka "Toaster":


https://www.batterychargers.com/en/p...ry-load-tester


The same basic model has been in production for years. This tester has a 100 amp test load. You hold the spring-loaded switch for 10 seconds and you watch the voltage under load. This tester has some limitations, and the battery must be fully charged before testing, but it is still very useful.


2) An Ancel BA101 capacitive tester:


Ancel BA101 Battery Tester | Ancel Scanner-Auto OBD2 Scanner


This one doesn't apply a resistive load like the toaster, instead doing some electronic magic. The battery need not be fully charged for testing. It determines both the state of charge and overall battery health. This one is far more accurate. It also has some other functions such as the ability to accurately check an alternator for AC ripple.


Here's an excellent article from a trade magazine, explaining some of the variables for testing batteries:


https://www.motor.com/magazine-summa...tery-of-tests/


Curiously, note how the author says the toaster has no place in a modern shop. I sort of agree, and if I could only have one tester, I'd go with the capacitive style. Still, I like to also run the test with the toaster, just being mindful of its limitations. Also, the capacitive tester I have is a budget entry-level model. A professional shop (the intended audience for that article) will typically have a much more robust pro-grade model.


Didn't mean to hijack your thread, certainly not my intention. I'd just love to hear more details of how you determined the battery was weak.

 

interstate are great. You just got a bad one then.
2 things from reading you description. Make sure you have pad material in the rear. Too thin and the motor overeaches and sets faults.
If you do have pads then the noise many times is caused by a bad hall effect sensor in the motor and it doesnt know where its at and again over reaches. Sometimes when i have replaced batteries i get this action and ill have to reboot the battery a couple times to get the park brake module to reset the system correctly

 

hi
machine gun sound is usually the actuator motor, more specific, the hall effect sensor
these are some good videos off facebook
cheers
joe.

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