Several months ago, my 2005 Mini Cooper S convertible (manual transmission) completely shut down while backing out of a friend's driveway. I towed it home and parked it in the garage, where it has sat since then while I worked internationally. I'm now home and will have a chance to work on it.


The car has ~75k miles and had not given me any other trouble. I had the car in reverse, with the clutch in, in anticipation of coming to a stop and putting the car in 1st. Then it died. Completely, totally, died. It was as if I had turned the key off. Subsequent attempts to start resulted in nothing: no dash lights, no clicks, no fuel pump whirr, no anything. I had a full charge on the battery (verified at the posts), but really wasn't able to do much other troubleshooting at the time.


So the first thing I'll try is both keys. I only had one key handy at the time and didn't think to try the other when this happened. I'll also try the "pull both battery cables off" trick and other ideas posted here:
https://www.northamericanmotoring.co...some-help.html

Thanks in advance for any ideas, and Merry Christmas.

 

Alternator would be my guess, charge/ replace battery and see if it starts. Mine did something similar a couple weeks ago.

Nik

 

Complete total darkness suggests normal operating conditions for the old British Leyland/Lucas system broadly known as 'The Prince of Darkness'. First place I'd look are the handful of primary power junctions, i.e. battery cables, engine bay earth connections and the like.

 

I'd check the ground wires....check the one by the passenger side motor mount first.

 

+1 on the motor mount cable .

 

No dash or interior lights suggests something further upstream of the engine strap. Since the battery tested fine with no dead/intermittent cells causing an under voltage, look at the GND strap. Take a multimeter and have a poke around. Test for a potential difference between the chassis GND an the engine GND. Test for 12V at both sides of the emergency explosive detonator which is located just after the battery and has a small fused bypass for the interior illumination/hazards.


BATT is red. Fused BATT is red with a stripe.
GND is Brown.
IGN is violet. Fused ignition is violet with a stripe.

The schematic is available here. http://www.bmw-planet.com/diagrams/release/en/ you need Java, Internet Explorer and Abobe's SVG viewer. If you get a Java warning you cannot negotiate add the website to Control Panel>Java Security

 

Update: problem solved. Turned out to be really nasty rust/corrosion in the 200A fuse box in the trunk. Apparently, there has been a recurring leak, allowing water to accumulate in the battery box. Cleaned it up as best I could and it fired right up. Now off to hunt the forum for likely sources of the leak.

 

On the convertible in the rear, its the seals on the upper trunk / convertible top. Or the main seal in the back. Also clean the gunk out of the trough when you lift the convertible top up to access the trunk. There are gaskets that wedge the corners and if water cannot drain under them and backup and overflows.

Mfg Part# 51137123438

http://www.ecstuning.com/News/R52_MINI_Cooper_Convertible_S_JCW_Rear_Trunk_Moldi ng_2005_2006__2007_2008/




And the main seal on the gutter , trough section . #2 51767178288

http://www.ecstuning.com/Search/SiteSearch/51767178288/



Rubber seal in trough.






Picture of lifted rear convertible top.

https://www.northamericanmotoring.co...ng-away-2.html








Last but not least check the convertible top itself for leaks or tears near the back at the seams.

 

FYI: A good household tool to clean corrosion from about any metal surface is an ordinary pencil eraser.