C5 2.0HDi 160hp Exclusive Tourer - battery charging

[mypinknee]

As a new member - I have some questions about diagnosing faults.
Can I get an independent diagnosis? Reading other posts there seems to be different kinds of diagnoses.

Is there anyone near me in West Gloucestershire who might be able to help.

The reason I ask is because my car has pretty faultless since I first drove it on January 1st 2011 - except for one thing - the boot won't always close or open electrically.
After a while I realised this might have something to do with either the economy mode or low voltage from the battery. After 3 years I was having starting problems because the battery was failing to take a charge and so the it was replaced under warranty.

Now 5/6 years later the problem started again. I have only done 55,000 miles and the car sometimes isn't used for a few days.

I took it to my local dealer who diagnosed an alternator fault. The battery was checked and found to be okay. They believed the alternator was not supplying sufficient current. I was told there had never been any official software updates for my ca and quoted £697 for a genuine new Citroen alternator or £391 for compatible one - both plus VAT. So I booked it in for the less expensive one. At the same time I made a request for help from Citroen on the basis there had been a fault with the alternator since the car was new. Yes - I am an optimist, and no they wouldn't contribute anything.

The car was examined and upon further investigation the garage found that there was a software update - which they did. This reset the charging rate for the alternator, so it was not replaced - I was happy about that!

I took the car away and found they had managed to lose the radio and remote control of the boot. I left it for a week while I was on Skokholm, came back to a flat battery. I got a jump start. Drove home and the next day decided I would replace the battery. This has been done and it is still early days to tell if the problem is now solved.

Is there any link between needing to recode the radio and the remote for the boot not working? The boot does open electrically - it is just the remote opening that has stopped working. Should fixing it take much time? Could I do it myself or is the garage responsible for making it work.

All comment gratefully received.

[Hell Razor5543]

Hi, and to the forum. While I am not going to be able to help you directly, might I suggest that you post up the VIN (for security reasons it will be obscured, but Moderators will be able to read it) so that it would be possible for Moderators with the right access can look up the details of your car.

There are also forum members who have Lexia clones that can read the ECUs of PSA vehicles (generic readers struggle with them), which can also make configuration changes. Not all of the members are active (so may not respond), but here is the list;

viewtopic.php?f=19&t=56452

[GiveMeABreak]

Is there any link between needing to recode the radio and the remote for the boot not working? The boot does open electrically - it is just the remote opening that has stopped working. Should fixing it take much time? Could I do it myself or is the garage responsible for making it work.

All comment gratefully received.

The common link is the battery.

When the battery is disconnected, some systems need to be reinitialised. The radio (depending on model) may need to have the date set, but nothing else and no, it does not need recoding - as they are VIN-coded to the vehicle.

Secondly, it may take a little while for the electric tailgate to reinitialise itself after a disconnection.

Whenever you disconnect the battery - it is essential to follow the guide to help reduce electrical niggles as a result fo the ECUs not being allowed to shut down properly before power is disconnected.

Guide and explanation here:

viewtopic.php?f=51&t=61997&p=601679#p601679

[mypinknee]

Thank you for your help.

So I guess the battery would have been disconnected at the garage. Wouldn’t the operators who installed the updated software have made sure the radio code wasn’t affected? Likewise the remote boot operation. The clock still tells the right time. May be as you suggest they did not shut down properly.

When you say it may take a while for the tailgate to reinitialise- this sounds very mystical! These problems occurred before I replaced the battery this morning. The replacement was done expertly by a local respected car electrics chappie. I am pretty sure he did not upset the car systems any further.

I know not to just uncouple the battery and re-connect. I have been told that many times, so have never done it. Can you tell me if this disconnection should happen what else might happen? Would I be able to drive the car at all?

Oh and the vehicle VIN is VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

There is no radio code - nothing to reset except check the time or date. You have the RD4 system, so there is no GPS, which means that you will have to manually adjust it after a battery disconnection. As I mentioned these Head Units are coded with the VIN of the vehicle and this does NOT get erased whether the battery is disconnected or not. It prevents the Head Unit from being installed in another vehicle without being recoded to that vehicle using a diagnostic tool.

To answer your other question. The reason your tailgate probably stopped opening and closing electronically, was because the battery was in a weakened state.

The C5 has a lot of Electronic Control Units and a lot of equipment that relies on a healthy battery. 4-5 years is about the duty cycle for a modern vehicle with a lot of electrical systems. When you consider there are systems that are actively monitoring the vehicle like the alarm, the locking and unlocking systems and the suspension ECU, the tyre pressure monitoring - all these are active for varying periods of time, so inevitably will use the battery.

The tailgate of course uses power without the car running, so imagine all that closing and opening without the vehicle running. So it is important to keep the battery in good condition.

Any time the battery is disconnected, some of the ECUs will reinitialise so it can take a while for some systems to reset. The tailgate is one, but it should automatically recall all the opening angle preferences the owner has programmed.

As for other garages, it’s pot luck what they do and don’t know depending on where you go. That’s why Citroen technicians have ongoing training / CPD that costs money to keep them updated on all the technological updates and new systems, including new electronic architectures.

With all the new adaptive and active safety technologies, there is no way independent garages can get access to the training on these without going on the official courses - which costs a lot. It’s another reason why the dealers are generally more expensive, because they have to pay to keep their technicians trained up.

[mypinknee]

Well, I took a look at the clock and it is telling the right time, and I tried changing it too to see if that helps, but makes no difference. All I get on the radio is a beep once a second. The same applies to any audio function. The remote control of the tailgate has not reconnected yet.

I also discovered that the spare key no longer works as a remote. I have no way of checking its battery, but it is less used than the main key and worked last time we tried it a couple of weeks ago.

I appreciate what has been said about mechanics and their training and I do not decry their efforts, or the cost of training etc. I guess I just miss the good old days when you could wander into the garage workshop and get firsthand feedback on problems with your car.

As regards the battery problems and it’s draining while the car is not in use, I have just ordered a solar panel and charger from Aldi. They have these on offer this week.
https://www.aldi.co.uk/solar-battery-ma ... lsrc=aw.ds
I plan to use it if I know the car will be standing for a few days by plugging it into the socket in the boot (this seems to remain live even with the engine off).

I am still curious as to why anything ‘should fix it itself’. I think it is a trip back to the dealer for me. Thanks for all the help.

[GiveMeABreak]

Now that you've described the issue further, something is definitely not right. The radio should not be beeping. Beeping indicates that it is not coded to the vehicle. Normally this should not happen whether the battery is disconnected or not as I mentioned previously.

I think something else is at play here. I would certainly question what your last garage did to cause this. Also, the fact that the spare remote key will not work is also an indication that it has lost its pairing.

Using the spare key that doesn't work, ensure the vehicle is open place the spare key in the ignition and switch the ignition on then press the lock button for at least five seconds release and remove the key from the ignition.

Then try and lock and unlock the car using the remote fob and see if that cures the issue for the fob.

[mypinknee]

Way hey
That worked - thank you very much.
and . . . . I held the key right next to what I assume is the sensor (above the rear view mirror) - pressed the boot button and - yessss - - the boot opened.
Not only that, I got the other key out and held that next to the sensor as well, and that too now opens the boot remotely.
So now I'm off to the garage to have them fix the radio.
Many thanks, Mike

[Gibbo2286]

You and I are near enough neighbours, I'm at Bream.

[mypinknee]

I just wondered if anyone else had tried this. During the winter with so many short trips and general lack of use I found I needed to put the battery on charge once or twice a month. So I eventually got bored with that and plugged in a solar panel. I plug it into the 'always on' power socket in the boot space when I get home. It seems to work well. I have not had to charge it any other way since. Hopefully I am not doing anything harmful.

[GiveMeABreak]

As long as it has some overcharge prevention protection for the battery.

[Gibbo2286]

I've been using one of these for the last few months on the C5, plugs into the obd port but also has the cigar lighter and crocodile clips adaptors. Works fine, I've left the car for twelve days without starting and it fires up first touch.

https://www.ebay.co.uk/itm/11380588315 ... 0deaf9e8b3

[mypinknee]

As long as it has some overcharge prevention protection for the battery.

Please can you explain how that might work. None of the solar panels I have considered buying have mentioned such a thing as over charge protection.
My panel was from Aldi https://www.aldi.co.uk/solar-battery-ma ... 1262369400 and says it is capable of providing 6W.
I have a couple of other batteries for a boat that I keep on charge all year round. One charges from a small solar panel via a Photonic Universe Solar Charger 20W 12 controller, while the other uses a Ring RSC508 Smart Charge 8amp Battery Charger. I swap them around occasionally and they seem to have kept the batteries quite well. One of the batteries is five years old now and the other four. They only get used for about a fortnight each year to run an electric outboard.

[GiveMeABreak]

Very simply, if the charge is not controlled, then over-charging can cause the electrolyte to get hot, and excess gasses are produced (oxygen and hydrogen). On an older, vented battery, this can lead to the electrolyte boiling away and damaging the plates. Most modern batteries are sealed however, and this can therefore lead to the battery bursting!

That's why most smart chargers have control circuitry to monitor the battery temperature and control the charging current, so that they can keep a battery at a floating or 'maintenance' level adjusting as needed.

If you have a constant uncontrolled charge going into the battery then you may be heading for trouble....

So check the technical characteristics or features of your solar panel charger to ensure that it has some sort of charging control circuitry and make sure it is suitable for your battery type and capacity.

[mypinknee]

Very simply, if the charge is not controlled, then over-charging can cause the electrolyte to get hot, and excess gasses are produced (oxygen and hydrogen). On an older, vented battery, this can lead to the electrolyte boiling away and damaging the plates. Most modern batteries are sealed however, and this can therefore lead to the battery bursting!

That's why most smart chargers have control circuitry to monitor the battery temperature and control the charging current, so that they can keep a battery at a floating or 'maintenance' level adjusting as needed.

If you have a constant uncontrolled charge going into the battery then you may be heading for trouble....

So check the technical characteristics or features of your solar panel charger to ensure that it has some sort of charging control circuitry and make sure it is suitable for your battery type and capacity.

I don't think the AA one or the one I have from Aldi are so sophisticated.
You would need some kind of sensor or feedback from the car battery.
Anyone know of a solar panel that does have such a sensor?