Water pump activated vehicle off
Good morning I have in my workshop a BMW 328i 2013 2.0 turbo
The problem is that when I turn off the vehicle completely and 30 seconds later the water pump is activated and that causes me to discharge the battery.
The fault code that it presents is CD8E10 Bus Lin- communication error
THis is a pretty common failure with the electric water pumps on BMW. They leak internally, and short out the controller board. Replace the pump. There is a bleed procedure for this. Do not use a funnel and let the engine run to burp the air! Key on fan on lowest speed both temps on highest setting hold the throttle to the floor for 20 seconds. for the next 1 2minutes the electric water…
Don’t the water pump and fans come on to aide in keeping the Turbo cool after vehicle shut off? I’m sure there is a timer and it’s supposed to go off. I would replace the battery as well if the water pump is shorted. It running constantly draining is probably working that battery too much.
Hello, check the Lin bus with a scope. If it don't look correct (12v square wave, communication bus) The pump may be shorting it out, causing the pump to stay on all the time. Do a energy diagnosis, see if there is a 30F fault.
Make sure to check all the DME power circuits for correct operation (Battery and Ignition power feeds). You want to make sure the ignition power feeds are fully shutting down when the key is off. I don't believe you'd have a LIN communication fault if it was just air in the system. Also, your pump is not constantly running (common when they short) it is coming on after 30 seconds which…