C5 all systems off.

[seanrx]

Hi.

For my fuse voltage drop test.

When my C5 is left to stand, how much time for all electrics to shut down?

I've been reading of two hours for some cars.
And they may boot up again! so there is a 'window' for testing fuses millivolts.

There is a definitive time for C5's?

[GiveMeABreak]

You just need time for the networks to sleep - but opening a door or fiddling with anything will wake up some of the networks.

So if you are doing a test where you need the battery connected as in your case and need to get into the vehicle, leave the door open but use a screwdriver to flip the door latch up so the car's BSI thinks the door is shut.

This will allow the suspension ECU to do it's thing and go to sleep and should not start levelling if you sit on the car seat for example. It will also turn off the internal lights.

So doing the above, I would wait 5 minutes after switching the ignition off minimum.

[ml11ML]

I noticed in my mk1 when waiting for the systems to sleep before disconnecting the battery that the little mileage display turned off with a few relay clicks after a few minutes of leaving the car alone - might be a usable indication?

[Peter.N.]

My X7's shut down in less that a minute.

Peter

[seanrx]

Thanks for replies and to read that the sus sensor will be off with 'closed' door.

This faff began 3 wknds ago, with the heavy rain and deep sill high puddles.

Have just disconnected the fog lights and door red lights, check if the battery drops then onto the fuse test.

[GiveMeABreak]

My X7's shut down in less that a minute.

Peter

You may think they do Peter, but there are systems that don't make any noise that take a little longer than a minute so lack of noise is not an indication. For example the EGR valve self- clean / check system operates a few times to help prevent sticking - which is one noise you may hear. The telematics unit fans can keep operating for several minutes after the ignition system switches off, etc. etc. The internal air mixing flaps can also operate.

The other ECUs don't make noise, so best wait for the 5 minutes to make sure everything has gone to sleep.

[GiveMeABreak]

Thanks for replies and to read that the sus sensor will be off with 'closed' door.

This faff began 3 wknds ago, with the heavy rain and deep sill high puddles.

Have just disconnected the fog lights and door red lights, check if the battery drops then onto the fuse test.

Don't forget you will have a drain regardless - the RCD circuit is always active - this is waiting for the remote fob signal to unlock the doors. Then there is the alarm - if you have an alarm system fitted, that is monitoring and active - like the internal volumetric sensors for example and the battery is also feeding into the alarm ECU and charging the alarm internal battery... so you will have this sort of activity going on unless you remove the relevant fuses of course when testing.

Direct TPMS systems (if fitted) will also poll the sensors at set times.

Then there is the engine ECU making recordings of fuel level and other stats that it writes to memory when the engine has been switched off.

[wheeler]

My X7's shut down in less that a minute.

Peter

Really? How have you confirmed that? Most PSA cars are around the 3 minute mark.

@ the OP have you done a current draw test yet? I wouldn't expect to see any more than 0.06 amps assuming thats got a factory alarm system.
Remember to disconnect the bonnet pin switch or leave something on it to hold it down to trick the car into thinking the bonnet is shut.
Were the fog lights staying on?

[seanrx]

Bonnet switch sensor also? Good to know this.
Was testing in line amps yesterday and it was high, I'll test again with that latch closed.

Fog lights are'nt staying on, operate normally. But are disconnected now so I can check volts thru the day.

I won't be testing today, raining. Always something.

[white exec]

Let us know what size of current drain you're seeing.

[seanrx]

Could be a while.

My brand new 2hr old DMM, I blew its 250ma fuse moving the probe lead from the 10a plug,(!) I forgot that reconnecting the battery gives a power surge.

Whilst in the 10a, I did have a reading of 0.01

[wheeler]

Fog lights are'nt staying on, operate normally. But are disconnected now so I can check volts thru the day.

Im confused, what do the fog lamps have to do with checking volts??

[seanrx]

Battery volts?
My battery yesterday dropped to 12.2 in nine hours.

Today, still at 12.6 after three hours.
If still like this late tonight, I'll plug in the fogs and check on Sunday.

[wheeler]

I still dont understand where the foglamps come in to this.

Have you had the actual battery tested yet? is the charging system ok?

[white exec]

In the 10A socket, 0.01 would mean 10mA (0.010 A), which is more than acceptable as a residual (quiescent) drain.
Anything up to 30mA is quite ok.

If you insert the meter (on 10A range), what does it read in the way of a surge — or is it all over so quickly that it settles to 0.10 almost immediately?