Battery drain - Fuses 36 and 42

Grumple said:
I've just been leaving it unlocked anyway... But even after being "dead" for days, opening the doors seems to activate certain systems.

So I guess the only way to truly test the current is to climb inside, close all the doors and wait while everything 'deactivates' fully before connecting the multimeter.
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Why not stand outside at the back with the key, and fool the car into thinking that the boot is closed by latching the lock with a thick screwdriver or similar? To get an accurate reading of draining current you might need to take the bulb out of the boot light if it still stays on. Then you can fully lock the car and wait 30 seconds for all the alarm and shutdown etc. to complete. Once the driver's door LED settles into its regular pattern of one flash every 4 seconds, everything should be asleep.
 
I'm not sure how to do that with the battery terminals both in place as normal (in order to lock the car etc...) - I've been using a multimeter between the negative terminal and lead whilst they're disconnected.

@PlasticMac has kindly offered to scan it tomorrow, so hopefully that can shed some light on it all!
 
Grumple said:
I've just been leaving it unlocked anyway... But even after being "dead" for days, opening the doors seems to activate certain systems.

So I guess the only way to truly test the current is to climb inside, close all the doors and wait while everything 'deactivates' fully before connecting the multimeter.
Click to expand...
The car is not "dead" if the battery is connected and there is still some power in it. That's why you can unlock all the doors with the key.

If you can, lock the car with the remote, with the hatch open. Then disconnect the battery. Close the hatch but put something between the hatch and the frame to prevent it from locking. After a few days test the battery.

RAB
 
RAB said:
The car is not "dead" if the battery is connected and there is still some power in it. That's why you can unlock all the doors with the key.

If you can, lock the car with the remote, with the hatch open. Then disconnect the battery. Close the hatch but put something between the hatch and the frame to prevent it from locking. After a few days test the battery.

RAB
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Hi RAB, meeting OP later, will follow the above, but just to clarify, with the hatch nearly closed, should the locking mech be closed with the a screwdriver, or is it OK just ajar?
Mac.
Edit: I intend to put my clamp meter on, so need hatch open a bit to see it, is that OK?
Not sure how the car knows, or thinks, the hatch is closed.
Mac.
 
PlasticMac said:
Hi RAB, meeting OP later, will follow the above, but just to clarify, with the hatch nearly closed, should the locking mech be closed with the a screwdriver, or is it OK just ajar?
Mac.
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No need to lock with a screwdriver. With the hatch open, lock the car with the remote. The hatch catch will be locked but open. Close the hatch but place something between the hatch and frame to prevent it from actually locking. Find something suitable before you disconnect the battery!

RAB
 
PlasticMac said:
Hi RAB, meeting OP later, will follow the above, but just to clarify, with the hatch nearly closed, should the locking mech be closed with the a screwdriver, or is it OK just ajar?
Mac.
Edit: I intend to put my clamp meter on, so need hatch open a bit to see it, is that OK?
Not sure how the car knows, or thinks, the hatch is closed.
Mac.
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You’ll need to trick the car into thinking that the boot is closed. I do this by getting the boot catch to latch onto the shaft of a screwdriver.

Cheers,

Tom
 
But surely you won't need to if the battery is to be disconnected! Are you not disconnecting the battery to check its state after a few days? If so, leaving the hatch open makes it much easier to re-connect. The OP has been leaving the car unlocked anyway.

RAB
 
If the battery turns out to be OK, the best way of checking for current draw is with a clamp meter. Much better than using a meter and disconnecting the battery.

RAB
 
RAB said:
But surely you won't need to if the battery is to be disconnected!
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Agreed. If the battery is being disconnected, then tricking the tailgate is needless.
If the quiescent current is being monitored using a clamp meter with the car locked, to diagnose a drain rather than a dodgy battery, then tricking the tailgate is handy.

Cheers,

Tom
 
The scan came up with what's to me anyway, a mystery.
The HVAC controller shows "too many errors, cannot continue"
So, I cannot clear the errors, as no comms to that controller.
Rest of the first scan shows nothing untoward, other than alarm triggers etc.
Need to clear those HVAC errors before a second scan.
Anyone know how to clear the HVAC controller, without VCDS?
At rest, current draw, car locked, and left for 5 minutes, is about 300mA, so there is a problem, I think.
The battery looks good, and charging current, after starting means the alternator is OK.
So clearing the HVAC errors is next.

Mac.
 
You could try removing the climate panel then unplug all the connectors and check for corrosion the plug everything back in securely. Could even try a replacement panel temporarily to see if that communicates.
 
You need VCDS or similar to clear the HVAC errors. There's always plenty of HVAC errors even when it's working fine! Ross Tech advice is to ignore the intermittent faults anyway.

The normal drain immediately after switching off/locking is about 250mA; this drops to about 50mA after a few minutes. My money would be on the battery (not keeping charge).

RAB
 
RAB said:
You need VCDS or similar to clear the HVAC errors. There's always plenty of HVAC errors even when it's working fine! Ross Tech advice is to ignore the intermittent faults anyway.

The normal drain immediately after switching off/locking is about 250mA; this drops to about 50mA after a few minutes. My money would be on the battery (not keeping charge).

RAB
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I have VCDS, which is where the "too many errors" message, is being generated! When you select the individual controller, to clear DTCs, it doesn't connect to the HVAC controller, so no way to clear them with VCDS.
So, it's a case of unplugging it, and leaving it for a while?
The battery sits at 12.7 volts with head lamps on engine not running, but we only checked for a short time. It did start on the button three times, so, the battery seems OK.
Once we've cleared the HVAC errors, we'll explore more deeply.
Mac.
 
audifan said:
You could try removing the climate panel then unplug all the connectors and check for corrosion the plug everything back in securely. Could even try a replacement panel temporarily to see if that communicates.
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No access to a spare climate panel, so unplugging is next step, I think.
Mac.
 
PlasticMac said:
I have VCDS, which is where the "too many errors" message, is being generated! When you select the individual controller, to clear DTCs, it doesn't connect to the HVAC controller, so no way to clear them with VCDS.
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Do you have a genuine VCDS lead? This post suggests that some 3rd party leads may cause this issue due to comms problems.
 
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