I really hope someone can help me here.

I changed the battery on my 53 Fabia VRS this week and measured the battery discharge current with the car locked. This was 180mA, which seems too high (this is taking 4.3 AH from the battery each day it’s not being used).

A friends ’06 car measured 130mA.

The central control unit appears to be responsible but the locking is working fine and there are no error codes for the unit in Vagcom.

The only fault picked up with Vagcom, which I don’t think is relevant to the discharge current, is:-

Address 08

-------------------------------------------------------

Controller: 6Y0 820 045

Component: Klimaanlage X0830

1 Fault Found:

01317 - Control Module in Instrument Cluster (J285)

79-00 - Please Check Fault Codes

The local dealer can’t tell me what the current should be and wants to charge me £100 to run diagnostics, but I don’t think diagnostics would measure current draw of control modules.

Does anyone know what the battery discharge current limit should be or provide any advice?

As I understand it, the ECU closes down slowly taking some 2 hours before getting to minimum power use. If you're measuring within the two hours, then you could get readings which are meaningless if multiplied by 24.

You need to wait at least 20 minutes after locking the car to test standby current drain. I can only find general data, so this is not specific for the Fabia.

Current Drain After Locking

120 to 250Ma

Current Drain with ECU in sleep mode

20 to 50Ma

I'll have a deeper root about the 89Mb Fabia Electronic section of the PDF manual and see if I can find any hard and fast figures.

I believe that the test requirements for checking when a battery discharges itself are that the battery is OK and interior lights and all electrical components in the vehicle are switched off. Disconnect the battery earth and check current. If this is a maximum of 25mA, test the battery. If above 25mA, isolate individual circuits by removing fuses one by one. In the event that it then drops to 25mA max, investigate for a fault in the circuit concerned. If it remains above 25mA, and no fault is found in the fused circuits checked, it will then be necessary to disconnect unfused electrical components, eg alternator and starter, and carry out fault finding using current flow diagrams. At that latter stage I would seek expert help!

Yes, from the electrical service manual 25Ma will no loads, but I believe that means doors not locked and alarm not set. Most after market alarms I have fitted draw 60Ma to 100MA when set, so I would say 125Ma MAX drain with doors locked and alarm set sounds about right, so 180Ma is a bit high.

So I would do the recommended test of drain check with doors not locked and alarm not set and see what reading you get. If 25Ma that would suggest (as you suspected) it will be central locking or alarm. If higher than 25Ma, start pulling fuses.

Thanks very much to all that replied. I didn’t realise it took so long for the unit to go into sleep mode. I’ve now made some more measurements and as suggested after 20 – 25mins the current does drop by 100mA.

Eg

Current Drain After Locking with courtesy lights extinguished = 180mA

Current Drain with ECU in sleep mode = 80mA

This is still higher than I would have expected (I was thinking ~30mA would be normal) but at least I should be able to start the car after a week of non use.

I’ll investigate more when time permits and report back if I find a fault.

Forgot to add that was no difference in current drawn if unlocked and not alarmed compared to being locked.

I have now established that the standard radio was the culprit, taking 50mA even when the central ECU is in sleep mode.

With the radio disconnected the total battery discharge is now under 30mA which is good.

I just need a replacement radio now.

Thanks for posting the problem fix, and well done.

Thanks for posting the problem fix, and well done.

I concur. .

and me too - all too often we wonder, "What happened" - thanks for taking the trouble to let us know.

Its taken me a while to remove the radio. (Kenwood extractors work a treat)

When pulled it out I discovered a Dension ice-link plus module plugged into the radio ICE connector. This is an ipod interface unit that I was unaware had been fitted which draws 55mA when the car is in sleep mode.

I don’t use an ipod so removed it and now have a battery discharge of 25mA and a working radio.

Its taken me a while to remove the radio. (Kenwood extractors work a treat)

When pulled it out I discovered a Dension ice-link plus module plugged into the radio ICE connector. This is an ipod interface unit that I was unaware had been fitted which draws 55mA when the car is in sleep mode.

I don’t use an ipod so removed it and now have a battery discharge of 25mA and a working radio.

Congrats ! and thanks for feeding the resolution back

Excellent piece of fault finding, well done mate.