Grand C4 Picasso 2015 - Electric handbrake stuck on

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Clungy05
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Joined: 30 Mar 2021, 09:23

Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Clungy05 »

Hi,

Just new to the forum but I have an issue and I'm after some help with a 2015 Grand C4 Picasso where the electric handbrake is stuck on.

Bit of history of the car-
Back around 2018, when it was still in warranty (just), we started getting a handbrake fault. We took it to the dealer, but there was no fault when we got it there as it had cleared, which is why we could get the handbrake off and drive it there. It was intermittent issue so difficult to get them to see it. At the time I'd read somewhere that the electric handbrake had to see a good voltage level before it would release, we suggested that to the dealer and they were happy to change the battery. We then had a couple of months with no issues, even the stop start worked again (which we'd forgot it even did that). Anyway, after a couple of months we started getting the same issue. Looking for potential issues I noticed that the 12V outlet in the back of the car had a USB plug in it. Despite this being switched (not always on), I thought about removing this as a way to solve the issue. I didn't think that would sort it, but worth a try. Unbelievably this did sort the issue and we had a couple of years of no issues with the handbrake system.

Then about 3-4 months ago it started doing it again. This time nothing was plugged in and draining the battery, so I disabled the auto handbrake as when it was in fault it could be 10 mins to fix, or it could be several hours before it would clear. Around 2 weeks ago it then started displaying the handbrake fault again, even when the auto handbrake was off. This prevented us being bale to engage the handbrake at all when parked. After the car sat parked for a couple of days (in gear), the fault would clear and all would be well until somewhere through the journey it would go into fault again. This time to develop a fault got shorter, initially 30 mins, then 10 mins and eventually less than a minute of driving would bring the fault on. Stupidly one day I went to the car, it had no fault and I put the handbrake on. It went into fault, has stayed in fault and I can't get the handbrake off.

I've looked over this forum and seen some suggestions about wiring that can be damaged and can cause a fault. That maybe fits with the fault getting progressively worse, and appearing quicker and quicker on the journeys. I've tried moving the wiring while my wife monitored the display, hoping it would complete the circuit and clear long enough to remove the handbrake, but no luck. I'd love to get the handbrake off to get it to a garage and let someone have a look at it. This is where I'm hoping someone can help.

Is there anyway of removing the handbrake when it is in fault, or can this only be done by removing the actuators that drive the parking brakes? I was hoping it may be able to be done with a diagnostics tool. I have seen some of these tools that claim they can remove the handbrake, but is that possible or does the fault need fixed first?

I don't currently have a diagnostics tool, but would be willing to get one. What would be the best option for this car? Also is there one that can remove the handbrake as claimed above or is that only when you are working on the brakes and have to remove it rather than overriding it when it is in fault?

Is it possible to get wiring schematics for this car? I've looked but can't find any. There are other electrical issues that the car has (keyless entry does not work anymore, passenger wing mirror doesn't retract, as well as some others) and I'd be quite happy to work my way through some schematics and try to get to the bottom of the issues. This may also help detect broken wiring and maybe bypass those to get the handbrake off, etc. Assuming getting these from the likes of Haynes manuals isn't a thing anymore?

Is there any mileage in the theory that the electrical handbrake system not working is related to a low voltage? Battery is about 11.5V with engine off. Should this not be about 12.6V, and is this enough to cause a handbrake fault? Unlikely I know, but given the history of the faults I've had it was something I thought might be possible.

Thanks in advance for your time and help.

Stevie

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GiveMeABreak
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Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by GiveMeABreak »

In a nutshell - yes, that battery voltage is way too low and this will play havoc with electrical systems.

I suggest you focus on getting the battery fully charged and make sure if removing it you follow the BSI Reset / Battery Disconnect / Reconnect Procedure or you may very well end up with electrical gremlins.

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GiveMeABreak
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Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by GiveMeABreak »

You are supposed to be able to manually release the electric parking brake as in the case of a battery problem:

With the ignition on or the engine running, to release the parking brake:
  • press the brake pedal,
  • while maintaining pressure on the brake pedal, briefly push the control lever.
The complete release of the parking brake is confirmed by the brake indicator lamp and the P indicator lamp in the control lever going off, accompanied by the display.

Note: If you push the control lever without pressing the brake pedal, the parking brake will not be released and a message is displayed.

Clungy05
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Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Clungy05 »

Hi Marc,

Thank you for the reply. I've tried to release the parking brake with that process but it is not working. That was what we had being doing to engage and release the parking brake for the last 3-4 months after I disabled the auto parking brake function.

Thanks for the link to your guide on the battery disconnection/reconnection. I'll have a look getting a battery charger to try and get the battery topped up. I did try connecting it to a another car battery via jump leads, hoping that if the voltage is part of an initial check it would see this higher voltage and be satisfied, allowing the parking brake to be removed. When the parking brake is in fault (as it is just now), as soon as you unlock the car and open the door it beeps and flashes a fault message. This didn't change when hooked up to the other battery. With regards to a battery charger, any to look at getting or any to be avoided? I realise it will have to be compatible with a battery used for start/stop, but after that is it pretty much see what is available and check the reviews?

Stevie

RichardW
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Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by RichardW »

Assuming the engine will start, just start it and leave it run for a few minutes, this will stabilise the battery voltage enough to see if that is the issue. Seems unlikely to me - a wiring fault or failure of one of the actuators is more probable. Removing the actuators is not too hard afaik - sure Marc posted the procedure a few months back. If you can't DIY, then if you've got breakdown with home start they should come out and release it.

Clungy05
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Joined: 30 Mar 2021, 09:23

Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Clungy05 »

Hi Richard/Marc,

I got a charger, connected that up and now the battery is fully charged, but still not allowing parking brake to be released. Was going to order a diagnostics tool to see what is causing fault, but not sure what is best to get. Can anyone recommend one? I see you can get them on eBay and Amazon, but are these easy enough to setup and use? I'd always thought that they would give you the codes on their own display, but the ones I've looked at have to be connected to a PC/laptop. Assuming this allows some additional functionality as well as just reading faults?

Unfortunately one of the kids has picked up Covid while at school so we are now in isolation. I was at the stage of phoning someone to try and pick the car up to take it to the garage to get sorted, but can't do that for another week or so anyway, so more time with it sitting in the drive so I'm now in the mindset that I want to get to the bottom of it without the additional costs of it having to be uplifted with the parking brake stuck on.

Stevie

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Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Hell Razor5543 »

I would suggest you take a look at the Easy Diagnostics Lexia system. It is a full 'octo-coupler' system (some of the cheaper units elsewhere have a partial system, and don't work with some PSA vehicles), and has a good aftercare support. I have an earlier unit, and would not be without it (unless I get a more up-to-date one).

Clungy05
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Joined: 30 Mar 2021, 09:23

Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Clungy05 »

Thanks James,

I'll have a look at that. When I have looked these I always worry as I have to connect to the laptop. My laptop is really slow, but I hardly use it as I have one for my work. Problem with that is that I can't download ant applications to it.

Stevie

Clungy05
Posts: 5
Joined: 30 Mar 2021, 09:23

Re: Grand C4 Picasso 2015 - Electric handbrake stuck on

Post by Clungy05 »

Hi,

I ordered a OBD reader, which arrived this morning. In a strange twist of fate when I went out to the car for the first time in several days (probably since last weekend) there was no fault present and I was able to get the parking brake off, only for the fault to re-appear. However it did allow me to release it so the car moves! Now left in gear in the drive!

I did read the fault codes with my Streetwise OBD II Scan Tool, and got the following:
Fault: 02 and Pending: 04
Faults - U0121 and U0140
Pending - U0073 P, U0121 P, U0140 P & U0140 P.

Would be grateful if anyone can help with these, and I can have a look if it is an easy fix. If it is more complex then I have the parking brake off so I can at least get it to the dealer or another garage.

Stevie.