2015 X5 35i - water pump running after car is off. - new battery and water pump

[X5NM]

Good morning,

i have a 15 x5 drive with a water pump that keeps running after the car is turned off.
i replaced the battery several months ago not knowing the water pump was draining it.
today, 4/9/24, I replaced the water pump and right when I connected power, the new pump started running. mind you the car was on the lift for 2 days so it was not warm. Not sure what to do next.

[Clifton]

There are few threads on here RE: battery replacement and water pumps that discuss strange runaway water pumps after a battery replacement.

For lack of better terms, the Water pump is wired outside of the normal key'ed power so that it can run to cool engine after you've locked up and walked away.

The down side to that is if you don't follow battery replacement procedures, you can short the water pump causing the run away effect leading to high battery drain.

Not saying this is your issue, but sounds very similar given both cases you mention connecting the battery.

[X5NM]

So I need another water pump and another battery?

[george1202]

Originally Posted by X5NM

So I need another water pump and another battery?

This happened to me a month ago, battery kept losing charge until it finally died (fortunately in the dealer). It was my water pump that kept staying on, dealer said faulty water pump and thermostat. They replaced it including battery. Not cheap. Hope you have warranty (around 2K here in canada). I would start by checking your thermostat on the water pump

[1004ron]

Originally Posted by X5NM

So I need another water pump and another battery?

Originally Posted by Clifton

The down side to that is if you don't follow battery replacement procedures, you can short the water pump causing the run away effect leading to high battery drain.

Did you follow the battery replacement procedures? - most cars these days need the Battery Monitoring System (BMS) reset after installing a new battery.

No way of knowing if that's your problem, but worth doing it to rule it out.

[Tomcat_F15_STL]

Originally Posted by X5NM

Good morning,

i have a 15 x5 drive with a water pump that keeps running after the car is turned off.
i replaced the battery several months ago not knowing the water pump was draining it.
today, 4/9/24, I replaced the water pump and right when I connected power, the new pump started running. mind you the car was on the lift for 2 days so it was not warm. Not sure what to do next.

Waterpump Replaced - or, Waterpump & Thermostat Replaced? Is the thermostat plugged in properly?

[X5NM]

Originally Posted by Tomcat_F15_STL

Waterpump Replaced - or, Waterpump & Thermostat Replaced? Is the thermostat plugged in properly?

I replaced the battery several months ago and did the reset with it. I replaced the water pump 2 weeks ago however I didn’t replace the thermostat.

[X5NM]

The car completely drain battery now, the active code I am getting is 20A701

[Tomcat_F15_STL]

Originally Posted by X5NM

I replaced the battery several months ago and did the reset with it. I replaced the water pump 2 weeks ago however I didn’t replace the thermostat.

oh, c'mon man!

[X5NM]

😂😂 thermostat causing water pump codes?

[stocktree]

Originally Posted by X5NM

The car completely drain battery now, the active code I am getting is 20A701

Did you change the pump yourself? You buy oem or aftermarket?

[X5NM]

Originally Posted by stocktree

Did you change the pump yourself? You buy oem or aftermarket?

Oem pump and changed myself as I own an auto repair shop. The code I got before o changed the pump was CD9010

[stocktree]

You see this thread?
Guy just had a bad replacement pump. Some additional info in there that may help.
https://www.bimmerfest.com/threads/n...ttery.1400098/