Audi 2.5 TDI heater plug light and flat battery

[scootermap]

please help Hello everybody I am having a problem on my 2002 2.5 TDI first of all I noticed the heater plug light coming on and then next was the flat battery after a day of standing so presume a leak somewhere,the battery is good as tested.Any ideas please.
regards
Graham.

[kite]

Check your brake lights

[a8 tech]

correct, if staying on the brake light switch is stuck in the on position, the glowplug light shows as there is a fault in the drivetrain which will store in address 03 and 01

[scootermap]

Thanks for the reply,I like the sound of that I hope its that easy I presume I have to sort the sticking brake light switch out if that is the case.
The brake lights will go out when the ignition is off so why the flat battery?
Thanks once again
Graham.

[kite]

Sort the switch then see if you still have battery problems.

[a8 tech]

The brake lights come on without ignition so if the switch sticks the lights are on and the battery drains

[scootermap]

I suppose I have to get my self sorted with some diagnostic equipment for future reference.
I will have a look at the brake light switch in the morning and hope that is the problem.
Thanks
Graham.

[scootermap]

Just re connected the battery to check brake lights but no evidence of that and I would have notice if they were on as my car is outside my house in view.This time when I connected the battery the airco fan kicked in so may be this is my problem the fan coming on randomly?
Any body had this and may be the heater plug sign is for changing could that be so.
thanks
Graham.

[a8 tech]

Check for a battery drain and eliminate the possible causes.A long draw mode test will show the time and duration of the drain.The fan is a good start and check foir a resistive circuit

[scootermap]

Its seems as though the fan is sorted but I still have the flashing heater plug light ,I have a new battery fitted so will have to see if that gets flattened by tomorrow.

[kite]

A fault scan might help.....

[scootermap]

Thats the next move I will have to get a cable and some software and learn how to use it.