"Parasitic" battery drain.

[dinnydubs]

Having trouble locating this, 1989 320i
The circuit fused by no 27 - interior lights central locking etc - is reading 4.2 on the 200m setting but when pulled the instrument cluster is still drawing 6.8. Having gone through all the fused circuits I've narrowed it down to the instrument cluster. Have tried several different clusters and all produce the same reading.
There is no aftermarket alarm system and I have disconnected the radio, the obc, the starter and the alternator, also removed the S.I board in case the batteries were causing the drain to no avail.
Was hoping this might shed some light, any advice or further questions welcome, plan to recommission the car after many years off the road.
Ty.

[Brianmoooore]

4.2 on a 200m setting is just 4.2mA if I'm interpreting your readings correctly. If so, you're chasing a non existent problem - typically the total parasitic drain will be 20 - 30mA, but up to 90mA is OK if there's equipment fitted that could justify it.

[dinnydubs]

Thanks Brian that solves my problem.

[martauto]

Thanks Brian that solves my problem.

Glad we could help and a big welcome to the zone mate

Mart.

[Brianmoooore]

Typical E30 battery has a capacity of 65Ah or 65000mAh, so at a drain of 4.2mA, it will be good for 15,476 hours, or getting on for two years.

[dinnydubs]

Thanks for that,

[dinnydubs]

Thanks for the welcome Mart.