Hi Guys,

I was able to purchase an S type 2.7D 2006 recently. A fantastic car and wonderful combination of engine/gearbox and ride. Only thing that is a PitA, is the EPB. I am struggling for weeks now to solve the issue, but I really need your expertise on this.

Problem: It says "cannot apply handbrake and handbrake defect" (dutch for broken).
Done so far:
new battery fitted
new module fitted
new motor fitted
new switch center console fitted.

But....still got the message (90% of the time, sometimes it works but i can't find a cause).

Current situation:
If you turn the ignition on and off, you hear the motor engage and disengage, so that works.
But I cannot use the switch in the center console. And I can't find why not.

Is it a real problem? I never use the parking brake, cause it is an automatic and Holland is a flat country. But the Dutch MOT is coming and i need a working handbrake.

So is there anyone in this forum who comes up with the one briljant idea i need and can't find for myself????

Thanks. Aldert

 

What happens:
1. the module activates the motor
2. it monitors (measures) the current
3. it monitors (measures) the time taken

It knows it should not take a long time for the motor to move the Bowden cable (the cable to the brake). Also, not too much current.

The module should have a code for what it is seeing is wrong - you will need a Jaguar or the like tool (such as IDS/SDD) to read the module.

Usually it is lack of maintenance but you have changed parts. Did you also change the Bowden cables?

 

Hi , yes changed the cables as well.
i have checked if the handbrake really engages as i turn of the igintion and it does. So curious thing is that that part is working.
thanks for the tip, i'll add the vehicle info.

 

Hello Aldert, and welcome to the forum.

One quick clarification about the switch on the center console, please. You said you cannot use it. Do you mean it starts the sequence but always gives you the fault message? Or does the switch do nothing at all, as if you'd never pressed it?

Re: the battery. You may find this thread of interest, even though you've already replaced it:

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


It doesn't seem your scenario fits exactly with the common failure mode. A few things to note, however:

New batteries typically aren't fully charged. Hook up an automatic charger every night for a week or so. See if the parking brake behaves itself with the battery fully charged at the start of each day. Inconvenient, yes, but free to try. Even with the car's charging system in good condition, it takes about 20 minutes of freeway driving just to replenish the energy used to start the engine. If the battery wasn't fully charged, and combined with numerous short trips, it could be significantly low even though the engine starts up just fine.

 

There is usually even more current (and power) available when you first start the car when it is cold - i.e. first thing in the morning. That's because the alternator is commanded to provide increased voltage.

So, that is a good time to try operating the EPB.

 

Switch does nothing at all (illumination works though), I even tried the calibration procedure, but because of the fact that he does not recognise the switch i can't calibrate it properly
.
But when i start the engine the EPB disengages ans i can drive away.

My daily travel to work takes me 45 minutes of highway, so battery should be ok. Battery gives 12.6 volts when engine is running.

Sometimes the fault is cleared for a short while (i can't find no logic in this), but driving for a couple of minutes does the message reappear, and i never use the handbrake!

One thing crossed ,my mind: can the brake on/off switch on the brake pedal interfere with the EPB module with this result?

 

Not enough when running.

Alternator should be quite a bit more - a volt or so.

 

+1 on that! Late model cars have the so-called smart charging system. You generally will see around 14.5V right after start, settling down to 13.5V or so within a few minutes.

 

hhhhm,, looks like i am looking in the wrong direction. Thanks, first thing next week to check.
The 12.6 was read on a device in the sigaretlighter, if accurate it indeed points to the alternator.

Thanks, i'll let you know!

 

Worth checking a few places - especially at the battery itself.

 

The voltage reading at the cigar lighter is known to be lower than at the battery terminals. A difference of 1/2 volt comes to mind, but I could be wrong on that...

 

Interesting. I keep an inexpensive voltmeter thingy plugged into the lighter on my '02. It shows a nice consistent 13.4 - 13.6 range. Maybe my experience is just a variation between cars?

Anyways, it's there just to keep a general eye on the electrical system while driving. For any actual electrical work, I always use a good handheld meter, not the lighter thingy. I've never checked the accuracy at the lighter, but it has been perfectly adequate for my needs.

​​​

 

No guarantee the voltage present is the root cause of the parking brake issue. However, a basic rule of troubleshooting is to fix the known faults first and go from there.

Also, for any electrical troubleshooting, always begin with a fully charged battery. I've seen several instances where a partially discharged battery leads you in the wrong direction, leading to perfectly good parts being replaced. I do not care to discuss how I know this.

 

Same as mine except it reads more on a cold start i.e. when the PCM boosts the voltage for a few mins.

 

Hi, I have charged the battery, checked the battery (12.7V) started the car and checked the alternator on the battery again (14.5V), so that looks ok, i think.
So back again to the problem. What can it be? again, today for half a minute after a stop at a shop, it worked correctly.

 

Thanks for indulging me and taking the time to rule out low voltage.

When everything behaves itself, does that include the manual switches, too? You had previously mentioned they were acting up, with no response from them at all most of the time. This points to two possibilities:

1) The switch module (or connection) is intermittent.

2) There's another fault present and the switch module is fine. However, due to this other unknown fault, the control module purposely inhibits the manual switches.

This is all conjecture on my part, so don't rush out to buy a new switch module or other parts. And unfortunately, I don't know which scenario is correct.

Look back at post #2. JagV8 suggested reading the faults with a Jaguar-specific scanner. You don't have to go to the dealer, as an independent Jag specialist should have the equipment.

One last though. Could you disconnect the cable from the rear calipers for troubleshooting? If either caliper was binding, maybe that is bogging down the actuator? Just a thought, perhaps others can weigh in.

 

Bought an OBDII unit:
fault codes:
C1094 - Parking brake apply switch - circuit failure
C1D00 - parking brake apply switch

What is meant by "parking brake apply switch"? if it is the unit in the center console, that one i have replaced.

Thanks, Aldert

 

Hi,
i have checked the harness and circuit on the switch in the center console. Harness is ok
With the ignition on i have 2.9V on the Red and Yellow and 4.9 volts on the switch itself.( release and apply part)

I don't know if this is correct. But...

Still same problem:
EPB motor engages when the ignition is off and key is out.
Releases when i put it into gear.
Gives the same faultmessages (Park brake fault; cannot apply handbrake)
Cannot operate it manually using the center console switch.

I am a bit out of ideas; anyone of you seen this before?

Thanks, ALdert

 

Aldert,

I am stumped, too. My only other thought is low voltage feeding the circuit due to a problem with the ignition switch. It's just a guess, but easy enough to rule out. See post #95 in this epic (and unresolved) thread for two simple checks to run:

https://www.jaguarforums.com/forum/s...3&postcount=95

 

Which red & yellow?

From Fig 05.2 I don't see what you're checking but you can see the various resistors and switches there. You may want to check at the module that each does as the circuit suggests - the apply & release look the same.