Hi everyone:

A few weeks ago my 2010 Cooper S died while driving to lunch. After a couple minutes she started back up and I managed to get back to work, but not before she died again. I get her towed back home to start troubleshooting. I checked the fuse and relay and they were both good, so I thought it was the fuel pump acting up. I read that they could overheat and shut down before complete disaster. That lead me to change the pump (and filter while I was back there), and she ran! I went to a job interview about 30 minutes away, no problem. On the way back however she died again. Luckily I had a Power Probe with me and I just supplied the pump with the 12vdc and got back to the house for more intense troubleshooting. Here's what I did. I unplugged the connector at the fuel pump and attempted to start it while measuring the voltage and got 11vdc (it's supposed to be battery volts 12vdc). Then, I load tested the circuit, again at the pump connector, and again got 11vdc (wiring harness is fine). Next, I disconnected the connector at the fuse box the one to the pump and tried starting her again and got 11vdc at the junction box. Next, I disconnected the connector at the fuse box to the DME, connected the pump back to the fuse box, grounded the relay and got 12.1vdc (battery voltage). Then I disconnected the connector at the DME tested the harness to ground and got an open circuit (the harness isn't grounded unintentionally). All this is to say that I think my DME is faulty. Does my logic make sense to anyone else? Have I made some error? Because I really don't want to buy a new one because I can't actually program it myself.

Thanks.

Oz

 

Check the ECU relay. the fuse box is next to the DME. Also, don't rule out a faulty fuse box (passenger kick panel) for water intrusion/damage.

Also, get obd reading even if you dont have a CEL. use a BMW/MINI specific reader.

 

OK, Do you happen to have/know where I can get the complete schematics for the DME and Fuse box?
How else would I check the fuse box for water damage?
Also, what would getting a ODB reading tell me specifically?

 

for schematics, navigate though newtis.info

if you have a sunroof, check for leaks, or if the carpet is wet/damp. you could open the fuse box and check for corrosion.

OBD codes can tell you if there is an error in the fuel delivery system or such

 

I don't have a sunroof specifically because I didn't want to deal with it leaking haha.

I've been to newtis.info, but I can't seem to ever find a complete schematic.
It's usually broken apart into the individual systems.

From what I've gathered, I should be able to check everything up until the high pressure pump without a reader.
You know, by checking voltage drop, bad grounds etc.
Do you know if there are any other things it would tell me?

 

When my countryman was acting up in a similar fashion, it turned out to be the fuel rail pressure sensor.

I also know of couple poeple having bad fuel that won't even let the car start.

My hardtop used to act funny because i forgot to plug the gas tank purge valve.

There was also a time where the throttle body was acting up. But for that i got codes.

Not sure if this is of any help, but evetually you'll figure it out.