Case study by Mario Rojas in NY. Permission Given to bring over.
This is a case study, but it's also exactly what I gave to the shop so that they can present it to the client.
2012 BMW 328i
prescan attached(in the email, not here lol)
left it overnight with the min/max feature and found a 1 amp draw
scanned it with a thermal imager to find the cluster was hot in the morning.
didnt know whether the wake up signal came from the fem or cluster, thought the fem did so i went to the fem and disconnected the connector that included the wake up signal wire
to find that the signal never dropped upon disconnecting it.
disconnected the cluster and the wake up signal dropped and the draw went away with the fem reconnected.
condemning the cluster.
also i have an ambient temp sensor code, the connector has become road rash, and the sensor is gone, along with the splash shield that it mounts to.
just in case i placed a resistor in order to mimic a functioning sensor, only to make sure that this was not keeping the cluster awake for any reason.
this allowed the code to clear, but did nothing to reduce the parasitic draw or to stop the wake up signal. draw persisted
opened the cluster but could not find anything burnt or visible wrong with it. RR&prog cluster, RR ambient temp... (More)