Z4 E86 coupe 2007/8 noise

[V-2f0ue]

Hi,

The battery is continuously draining at 1.5A when everything is turned off. Under the rear possibly to the nearside I can hear a low level hum/whirring sound that disappears when battery disconnected. I haven't had it up on the ramp yet but would welcome any ideas what I should be looking at/for.

Also, the battery went flat, so the car is now in transport mode. That's another problem, no aircon.

[InitialDave]

Fuel pump?

[V-2f0ue]

That was my thought but why would it be running when the ignition is off and key removed, doors closed and locked??

[Wills2]

Not experienced that on mine, but could be the RDC control unit according to Google that is located at the rear they can fail and continue to "work" draining the battery causing that noise.

[InitialDave]

V-2f0ue said:

That was my thought but why would it be running when the ignition is off and key removed, doors closed and locked??

A lot of cars prime the fuel pump on unlocking, so my thought was it could be stuck in a cycle of doing that constantly for some reason.