BSI power drain

I think I've finally traced my battery drain to the BSI, if I disconnect the power supply to the BSI the battery doesn't drain, I pulled all the fuses today and after a few hours the battery was dead. Strange thing is there is no amp draw immediately or half hour after the car is locked so somehow it's happening well after shutdown( how I don't know ) but the BSI is drawing a current. Possible the internal relays are sticking or switching on. Does anyone know how to test them.

Yeatesy wrote:I think I've finally traced my battery drain to the BSI, if I disconnect the power supply to the BSI the battery doesn't drain, I pulled all the fuses today and after a few hours the battery was dead. Strange thing is there is no amp draw immediately or half hour after the car is locked so somehow it's happening well after shutdown( how I don't know ) but the BSI is drawing a current. Possible the internal relays are sticking or switching on. Does anyone know how to test them.

I don't think you are going to get far with the internal components of the BSI. Most of it is computer controlled solid state relays with only a couple of classic mechanical relays.

To test a mechanical relay, remove it, apply a current across the coil and monitor the switching (continuity) of the contacts. If you don't have the equipment available you won't be able to test the solid state relays and their control circuits.

Have you tried unplugging the separate circuits from the BSI if the fuses don't help. It may not be the BSI drawing, but one of the circuits connected to it.