Battery drain on disco 1 suspect MFU unit fault

Hi I've been having problems with my disco battery draining overnight. Its got a short but i'm having trouble finding it. I've pulled the negative terminal on the battery and and put a multi meter across it and its pulling about 1.5 amp. Pulled the fuses one at a time and the main short is on the tow bar electrics fuse 6 on the satellite B. When this fuse is pulled the short drops to about 0.1A. This is still killing the battery but slower. When fuse 12 for the multi function unit on the main board is pulled the short drops t about 0.01A. I've disconnect the tow bar electrics at the drivers side rear compartment behing the lights but it is still pulling about 1.5A. So its not the wiring at the tow bar.
I've checked the earths that i can find and been through the forums, can any one help?
Can anyone tell me what the normal draw on the battery should be when the car is shut down?
Can some one point me in the right direction of where to look for the short?
Would a MFU unit fault cause this type of fault. Did not want to just replace it yet with out confirming as they are expencive.

Hi Rob welcome to the Forum.

Once fuse 12 is pulled out and the ignition switch is turned off the MFU is isolated, there isn't any voltage going to the Unit so that can't be the issue.

The alternator has been known to be responsible for draining the battery overnight if faulty, there is info on testing the alternator and current drain already in the Forum, use the search at the top of the page, as that subject comes up now and again.

discool said:

Hi Rob welcome to the Forum.

Once fuse 12 is pulled out and the ignition switch is turned off the MFU is isolated, there isn't any voltage going to the Unit so that can't be the issue.

The alternator has been known to be responsible for draining the battery overnight if faulty, there is info on testing the alternator and current drain already in the Forum, use the search at the top of the page, as that subject comes up now and again.

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Hi thanks alot ill have alook

rob parsons said:

Hi thanks alot ill have alook

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Hi ive disconnected the alternator and am still getting a short of 1.5a. I disconnected the radio as this appears to be fed from the tow bar fuse aswell but was still gettind a 1.5a short. I also disconnected all 3 interior lights and the short dropped a litle bit with each light. Got it down to 0.1 a. Not sure why it is doing this. And why it is shorting on the tow bar lights fuse and not the interior light fuse. Any ideas?

Just pull out 20amp fuse 6 on the upper aux fuse panel, it protects the radio, clock, alarm, interior lights and the trailer socket 12v aux supply.
The tow bar lighting circuits don't have their own fuses, as they are just an extension on the normal lighting circuits which are already fused.