Hope this helps someone.

I fitted new front discs to my E60 M5, while I was there I thought I'd fit new pads aswell. The old pads had plenty of meat on them but its only sensible right ?

All went well and while I was parked up a couple of days later, I thought I'd http://www.bimmerfest.com/forums/showthread.php?t=436418" rel="nofollow - reset the mileage count down on Idrive for the front pads. I did that and thats where it went t*ts up. From having no faults at all, the car started bonging and a message saying "get yourserlf into a BMW dealer son!" wouldn't go away. It was saying that I had to have new front pads fitted but I'd already done that 2 days and 20 miles ago. 

After a lot of research, I found out that the pad wear sensors have a http://https://wiki.bentleypublishers.com/display/tech/Brake+pad+wear+sensor+testing+BMW+5+Series+E60" rel="nofollow - 2 stage warning . The first stage reduces the miles left on the Idrive and the 2nd stage is a "get yourserlf into a BMW dealer son!" I found out that if you measure the resistance across the terminals of the pad wear sensor, if you get a short or 0.0005 (ish) reading the sensor is ok and stage 1 hasn't been triggered. If you measure in the region of 470 Ohms then stage 1 has been triggered but not stage 2. if there's an open circuit or no reading on the meter, stage 2 has been triggered and the sensor must be replaced. 

I decided to change both sensors as it was a cheap deal weekend at Eurocarparts. £25 for 2 isn't bad so I then set about changing them. After they were changed, all I had to do was reset the Idrive right ?? WRONG!!!! It just wouldn't reset

Loads more trolling through then net and the wheels back off to check the resistance of the new sensors and it still wouldn't reset.

Ages ago, I bought one of those blue cables and the INPA software so I installed it on this laptop and thought all I had to do was reset the fault codes. After plugging it in, I could see the fault, clear the fault and it just kept coming back. Off with the wheels again to chack the connections and I'm now thinking that the car wiring is at fault before it plugs in to the sensor. 

I'm now thoroughly hacked off and come back in to the house and have one last look on the net. The first page of the new search fired up  http://www.m5board.com/vbulletin/e60-m5-e61-m5-touring-discussion/288073-diy-e60-m5-reset-brake-pad-sensors-using-tool32.html" rel="nofollow - this page . I followed this guys instructions and hey presto, up it came and its now sorted. Thank fork !!!

I hope this helps some of you.