Mini Cooper-Electrical Problems and Timing Chain Faults

Long technical explanation follows...grab some coffee.

Let me first share that we do not post these things to embarrass anyone, nor do we take delight in the mistakes of others, we're not perfect, we've just learned when to ask for help. We rather share these tech tips so that others may learn, and hopefully avoid the same problem.

Now, back to the Mini!

Car presented with no-start condition. Engine would crank over, but no start and run. Acted much like a theft deterrent system was shutting down the car, what Mini calls the "CAS" or Car Access System. Nearly every module on the car was chock full of multiple faults, including some anti theft faults, all of which cleared out and verified.

So what happened to this good little car? A combination of things, here's our theory. The car came from two other shops, along the way we discovered that someone had apparently reversed the battery leads, or perhaps attempted to jump start the car backwards, hence damaging the engine computer or DME. The battery was very weak, likely from extended engine cranking, and we had to replace, so we know that somewhere along the line someone had to use a battery charger or booster.

What made this doubly difficult is that either they did not know that happened, or they did not want to share it. Rather that, just admitting they were lost, they apparently attempted to "fix" the problem, removing and checking every fuse and relay on the car, pulling modules, then putting some back in the incorrect order, one relay was even missing. When that failed, the car was towed to us.

The repair was made even more challenging in that we had to fix the damage caused by well meaning, but misinformed folks, before we could get to the root of the problem. We'd fix one problem, only to be confronted with another.

The root of the problem, the camshaft timing was off, enough not to damage the engine, compression was good, but enough to prevent the car from starting and running. We put the camshaft timing back in sync, and the engine started like a charm. 2007 and later Mini timing chains are the weak point on the car, and this may have happened when the car was towed, or bumped when in gear. There are some additional items we need to iron out, but that's the basics.

These type of problems come up from time to time, having accurate information about what really happened is 50% of the battle, product knowledge and training is the other 50%. The one good thing that comes out of challenges like this is the tremendous satisfaction of solving a problem, and a great appreciation for fellow shop owners and professionals we collaborate with.

http://www.atlanticmotorcar.com/case-studies/2013/02/

 

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