Kahl 0 Report post Posted Wednesday at 02:47 AM Afternoon, I have a 2011 e90 335i with an N55. I've noticed this last week that the water pump will start to run about 5secs after unlocking the car in the morning and will also remain running for a while (I haven't timed how long) after the car is shut down and locked. I know its the waterpump because it's shooting a good stream into the expansion tank when it does this.... and of course I can hear it. I've read that the control electronics inside the pump can go on the fritz. MHD Code check shows "378F - BSD. message, electric coolant pump: Missing", obvs it's nor completely cooked because it's pumping, but I'm guessing it's pumping 100% ALL the time now? I have also noticed the water level in the expansion tank dropping, about 700mls in 6months maybe, could it be that my pump has an internal leak that has impacted the internal controls?? I feel like I'm about to replace the pump but any and all suggestions welcome Cheers, Karl Quote Share this post Link to post Share on other sites
