All you electronics boffins..

[Peter.N.]

The saga with my C5 that runs the battery flat in a few days continues, as I already mentioned the consumption with everything off varies cyclicly between about 150ma and one amp over a period of about a minute, sitting in the car today I noticed about once a minute there was a noise behind the instrument panel like a motor doing a couple of revolutions, this again happens about every minute, at the time it starts the speedo needle moves hard against the stop for a second and then back to normal, if you turn the radio on, when this phenomina occurs the radio goes off for a few seconds and the on again. I have had some queer faults on TVs but nothing like this

Peter

[CitroJim]

How bizarre Peter

Yes, compared to this the old tellys were easy even if they had us scratching our heads at the time...

Sounds like the BSI is not going to sleep properly but that's just a guess...

[myglaren]

How long was it before you heard the noise?

I have noticed similar noises, usually after about five minutes. I think it is the car going to sleep (closing the ventilation ports)

The car should 'go to sleep' a while after being locked. Economy mode should only be invoked if you leave something on (radio/CD) which mine will do after 45 minutes. After that the plipper will operate the locks but nothing else will work until the engine is started again - lights won't flash on unlocking, windows won't respond to the remote.

Are you sure the battery is fully charged? C5s have a reputation for electronic shenanigans if the voltage drops a bit.
Currently, mine always flags an airbag warning after the first start of the day, which vanishes on subsequent starts.
This is due to slow starting that is dragging the voltage down for a little while.

Charging in the car may not be adequate if on shortish runs, a good overnight charge may make a difference.

Do be aware of the lunatic requirements for removing and reinstalling the battery though.
Battery removal may also clear the problem if it is the BSI at fault.

[Gibbo2286]

Are we sure Peter's not just hearing the suspension pump running if the car's unlocked and he's sitting in it?

[cachaciero]

Are we sure Peter's not just hearing the suspension pump running if the car's unlocked and he's sitting in it?

No he's not there is something which makes the noise he described when the system goes into economy mode, I suspect that it is cycling into and out of Economy mode for reasons which I can't imagine.

Peter assuming that you got all i sent you yesterday in the PDF that covers multiplexing there is a description of the electrical system, what happens and whe,n should help you understand what SHOULD happen. The first thing that needs checking is the BSI for any faults second Economy Timeout configuration setting in the BSI, and yes you will need your Lexia.

cachaciero

[dnsey]

It seems likely that as the system enters economy mode, something is triggering it to 'wake up' again.
A similar phenomenon sometimes occurs with PCs as they go into standby.
The business with the speedo is a bit odd, though.
If you leave the ignition switch on position 1, does the display show 'economy mode active' as the pulse occurs?
Does the cycling start as soon as you switch off, or some time afterwards?
Do you have any non-OEM equipment fitted (radio or alarm, for example)?

compared to this the old tellys were easy even if they had us scratching our heads at the time...

True, but modern ones can do very similar stuff to Peter's car, and there's often even less service data available!

[Peter.N.]

Thanks for all you comments again. The car had a new Yuasa battery on it when I got it and the alternator had been checked, I meant to check the charging voltage myself but forgot but I have also had it on the fast charger as it wouldn't start today.

Yes, it comes up with 'economy mode' when you switch to the first position. The cycle starts almost immediately you stop the engine, after the hydraulic pump has stopped anyway and continues indefinitly, well I checked it for three or four hours anyway.

also Yes, it does have an aftermarket radio fitted, well its actually a Blaupunkt DVD/CD/Radio and I had thought of disconnecting it as it is being switched on and off by whatever this problem is, switches off for two or three seconds every minute.

Cachaciero.

Have not recieved files yet.

Peter

[dnsey]

OK, I think it would be worth disconnecting the radio to see what effect, if any, that has.
It's quite possible that it's been connected in such a way that it's inadvertently sending a 'wake up' signal to the ECU as it's turned off by Eco mode.
The fact that the cycle starts immediately is a bit suspicious, though, and does suggest that the voltage is seen as low by the ECU. It would be well worth checking the voltage at a convenient point (lighter socket?) with the lights on tho load the system, and the engine stopped.

[cachaciero]

OK, I think it would be worth disconnecting the radio to see what effect, if any, that has.
It's quite possible that it's been connected in such a way that it's inadvertently sending a 'wake up' signal to the ECU as it's turned off by Eco mode.
The fact that the cycle starts immediately is a bit suspicious, though, and does suggest that the voltage is seen as low by the ECU. It would be well worth checking the voltage at a convenient point (lighter socket?) with the lights on tho load the system, and the engine stopped.

I would second the radio theory.

Re files they were attached to the e-mail I sent and to which you replied, will try again.

cachaciero

[Peter.N.]

sorry I must have read the mail and then deleted it. I will see if I can recover it.

Peter

[Peter.N.]

Found it thanks - but can't open it.

[Clogzz]

After stopping the car and sitting in it with the key out, I also have the speedo milling backwards after about three minutes.
There are other sounds going with it, like relays clicking in the centre console and glove box areas, and even one in the back seat.
The back seats are in the junk room for now, and that sound is still there.

When returning to the car, turning the key to position 1 causes the heater flap motors to turn when the car is sitting in the shade after having been turned off when parked in the sun.
You can’t even turn the heater controls off in the C5.

My economy mode starts after half an hour, and it’s not affected by the state of the battery.

[Peter.N.]

Thanks all IT WAS THE RADIO!! Its now settled down to a steady 36ma, can anyone tell me why?

Peter

[dnsey]

The OEM radio is in constant communication with the BSI. via the network.
When an aftermarket unit is fitted, many people just connect like to like, and hope for the best. In some cases, they get away with it. In others, as you've found, the networking is compromised. Most likely, as the BSI enters economy mode and removes power from the radio, it (the radio) produces a voltage spike, which would be quite innocuous in a non-networked system. However, if that spike gets onto the network, the BSI will interpret in an unpredictable way - in this case, as a signal that something needs the system to exit eco mode, which wakes it up again. Thus a a never-ending feedback mechanism is set up.
You can almost certainly still use your radio if you take it to it to a competent auto electrician or ICE place to have it refitted correctly.

[Peter.N.]

Thanks for the explanation. I know the later TVs started to have a BUS system but never really had any problems with it. The radio seems to have just been plugged in to the existing connectors I don't think anything has been modified, I know the new radio I have for the 406 needs coding, it bleeps, hopefully I can do that with the Lexia once I get it going.

Peter