C5 Battery

[Sunderas]

Hi all.

I am thinking of replacing the battery on my C5 as I have no idea if it is not the original one or just a dodgy replacement as the economy mode kicks in a few seconds after the engine has cut off.
I don't think it is the alternator as it has been like this for a while and never let me down.
I am not very experienced in swapping batteries as the only time I needed to do it on my old Fiesta it was still rocking the original Motorkraft one. It lasted a shocking 8,5 years.
Annoyingly enough, the moment I've removed the battery and placed the new one the security for the radio kicked in and requested a code.
Now I think that you guys can give me some pointers on this task and how to do it (I have no shame in asking such a basic question ), but my main concern remains with the possibility of getting the system locked and needing a code. Can someone please clarify if this is what is expected to happen? If so I am screwed as I have no Idea where the code for this radio is...

Thank you.

[GiveMeABreak]

First of all, economy mode will Kick in normally and it won't always be the battery. I have a brand-new high-capacity battery, and I rarely get more than two minutes of use before economy mode kicks in regardless of the battery condition. I just put it down to the car, but I do have a lot of electrical equipment on the car.

Next regarding the radio, there is no radio code like Ford on the C5. The radio is coded to your vehicle via the last eight digits of the VIN number. Therefore when you change the battery you need not do anything. What you do need to be aware of is the BSI reset procedure when disconnecting and reconnecting a battery. Failure to do this will cause electrical problems. It is widely documented on the forum.

[Sunderas]

Thank you for your feedback.
Might I know what is the BSI reset procedure? How does it go? Is it something complicated? Do I do it before removing the old battery or after?
Do I need to sacrifice a chicken to any deity in this process?

If it is not followed what are the consequences of failing to follow it?

Thank you.

[GiveMeABreak]

No sacrificial chickens needed on this one!

The BSI reset just allows the car's main computer and ECUs to shut down properly, before disconnecting the battery so they are in a 'sleep' state. When the battery is connected back up the pricedure allows them all to reinitialise properly, preventing any problems.

The procedure is in my post here:

BSI Reset / Battery Disconnect / Reconnect Procedure

[Monkeyfeet]

On the subject of going into economy mode soon after switch off - I've not bothered with it myself but isn't there a procedure for measuring battery voltage and updating the voltage value?
It could be reading the battery voltage as too low.
DMM and Lexia required, but don't think it takes long.
Might even try it today if it'll be of any use as a guide, let me know.

[GiveMeABreak]

On the subject of going into economy mode soon after switch off - I've not bothered with it myself but isn't there a procedure for measuring battery voltage and updating the voltage value?
It could be reading the battery voltage as too low.
DMM and Lexia required, but don't think it takes long.
Might even try it today if it'll be of any use as a guide, let me know.

Apart from measuring your actual battery voltage, there is a Battery Charge Status Control Unit in the X7 that monitors all this, so there's not a lot to be done on this model. My battery is brand new and fully charged - makes no difference, the car decides when it turns everything off and there are no settings on Lexia to change the Economy mode timings on the X7 either. It does increase slightly the longer the drive you do, but in real life, if I've done a motorway drive for a few hours and not used any accessories after switching off, then go for a drive for 5 minutes down the road, stop and turn radio on, it will only give me usage of 30 seconds to a minute before going into economy mode again. I just live with it - it's all documented about the time you get related to the immediate previous journey you've done.

[GiveMeABreak]

There was a replacement Battery Charge Status Unit for the X7 - new part number: 9801031580
which I'm guessing probably improved things somewhat - but at £80 a pop plus the hassle of changing it, I can live without it!

It's probably worth a mention that I have the electric seats with comfort setting that slide to allow driver entry and retract to allow exit that work when the key is taken out / ignition started, plus the Navidrive 3D system is a behemoth of a unit which needs a lot of cooling, so that system's cooling fan stays on too every time the car is switched off regardless of economy mode - so it allows certain things to run.

[Paul-R]

From what I've read that monitors the current flowing in and out by measuring the voltage across a resistance, not the voltage as such. So, if the battery is charged up incorrectly (directly to the terminals) or replaced by a different battery then there has to be a procedure to reset the parameters. I think this is what Monkeyfeet is referring to.

As a battery ages then it will not be able to give out as much current as went in so this must also be accountable somewhere.

Incidentally, if you charge the battery up in the correct manner so that the Battery Charge Status Control Unit is in circuit then that surely implies that the BSI has to remain awake all during that time the battery is being charged?

[Paul-R]

... the electric seats with comfort setting that slide to allow driver entry and retract to allow exit that work when the key is taken out / ignition started,...

I had that engaged for a short time and then switched it off as I realised that if you have the rear seats down and something behind the driver's seat then there's a possibility that the "something" could be crushed as the seat mindlessly moves backward.

[GiveMeABreak]

From what I've read that monitors the current flowing in and out by measuring the voltage across a resistance, not the voltage as such. So, if the battery is charged up incorrectly (directly to the terminals) or replaced by a different battery then there has to be a procedure to reset the parameters. I think this is what Monkeyfeet is referring to.

I don't think so, as the unit has both a voltage sensor and a power sensor incorporated into the unit so will always know what the status of the battery is and informs the BSI accordingly. It undertakes the following (some of this from C4 Owners):

• Monitors the battery voltage in the off and ignition on statuses
• Monitors the battery current in the off and ignition on statuses
• Monitors the battery temperature in the off and ignition on statuses
• Determines the battery charge status on the off and ignition on statuses
• Determines the battery health status in the off and ignition on statuses
• Informs the BSI 1 of an insufficient battery charge status
• Informs the BSI 1 of a critical battery health status
• The battery status sensor is supplied by a protected permanent battery+ supply .
  
  The battery status information is available and distributed by the battery status sensor at the request of the built-in systems interface during the following life phases :
• At the wake-up of the BSI 1 alone
• At the partial and main wake-up of the IS CAN
• At the wake-up of the COMFORT CAN or BODY CAN 9

I have a new Bosch S6 AGM battery Paul - so it is designed for extreme electrical use, has a long service life, has low self discharge rates, and tolerates low temps well, a charge up to 5 times faster than a flooded type and can deep cycle. So I have no issues with the state of it.

Incidentally, if you charge the battery up in the correct manner so that the Battery Charge Status Control Unit is in circuit then that surely implies that the BSI has to remain awake all during that time the battery is being charged?

I have only ever taken it off to check the charge and perform a top-up, which it didn't need as it was fully charged (using an AGM battery charger). But if charging it on vehicle (which I prefer not to do), yes you should connect it to the crimped BCMU (Battery Charge Monitoring Unit) terminal. Regarding the BSI - they do say that when you are checking the battery status using their Midtronics tester, that you should do this with the car at 'rest' with doors shut to allow car to 'sleep' to get an accurate reading. Similarly, this would be the same when charging on the vehicle - allow BSI to sleep first

[Paul-R]

Thanks Marc. it does beg the question of how intelligent, if at all, the Battery Charge Status Control Unit is. And whether it draws power all the time so it can monitor the battery.

[GiveMeABreak]

Yes, interesting point Paul, although it says it monitors the status of everything with ignition off - I'm wondering if this is still the case when the BSI and other systems are shut down - but then again, as it says in my last post, it has a permanent battery+ protected supply, so I'm guessing it must operate all the time, much like the circuit for the central locking and alarm system for example. I can't seem to find any information on why the BCMU was replaced, but at £80 I would expect there to be more than a resistor in there!

[Paul-R]

Not heard of the principal that you charge what the market will bear?

[GiveMeABreak]

Ok, how's this for complete ridiculousness: £42 for a new LDS reservoir, but how about £56 for this little piece of chrome finish extracted and blown up - not more than 1 x 1½ inches!: I leaned over to the back seat and heard a 'pop' - and sure enough the plastic lug as gone walkabout. I can live with it - especially as I can buy the complete seat for £150 from a breakers (minus air bag)

[Stickyfinger]

Ahh....the joys of plastic

I think the boot "Nets" and the tiny plastic clips on the surround were supplied from the factory broken