I'm searching high and low for this relay, cause I don't hear my aux pump going anymore after shutting down and don't want to toast this turbo.

Anyway to jump twelve volts to see if it's still working. I know there are 3 wires going in which are the neg and positive?

 

Did you check in the fuse panel under the hood?

 

Yup first port of call but those relays are labeled as R1-7. 4 green and three black.

 

Aux water pump is on 40A fuse together with ABS. That's the reason why it's catching fire and there was a recall on this topic because there is no way fuse is going to blow before the tiny pump wires do. When the pump fails it stops working and wires are potentially melting which is the cause of random Minis burning down. I was in the car luckily when that happened to me and managed to save the car with limited damage. I would advise anyone with R56 Cooper S to install in-line fuse on the aux water pump positive lead.

 

That's scary news about the aux pump wiring. Sounds similar to the r53 power steering fan/radiator fan issue. Jeez Mini, just give us a few more circuits.

How much current does the aux water pump draw? I have to replace my aux pump and might as well add an in-lne fuse while I'm at it.

 

Don't know exactly how much current it draws, I couldn't find any information online, so I've put 10A fuse and it's working fine.

 

Which line supplies power to the aux water pump? I've pulled my engine for maintenance so can't directly test voltage, but I'd like to add the fuse while I have easy access to the wiring harness.

 

Engine wiring harness is completely different for n14 and n18. On n18 there is a wiring branch that splits right after ECU that's branching out to 3 different devices: aux water pump, o2 sensor and blow-off valve. Aux waterpump is directly under the turbo down low on both n14 and n18. I've added the inline fuse right after where it branches off. Try looking for a connector that fits the aux water pump. I can't remember which particular wire is positive on that connector but it's most probably red one.

 

Fun fact, just saw in BMWTIS that they introduced additional fuse for aux waterpump at certain year. So the recall that BMW had for 2008-2011 for Mini aux pump catching fire they just changed for the new version of aux pump and then silently added fuse for later models. Way to go BMW.