Except R1 should be on the other side of the diode, otherwise the zener will drop the 12V bus down to 3.3V or blow up, whatever comes first.
Your 100% right zetski210. Stupid me wasn't thinking at the time. Thanx for pointing it out, otherwise people who may have tried it may have had a burn out.
Here's a fixed up version. Its rough though. Couldn't be fagged doing it properly:
I have to admit that your circuit (zetski210), would be much more stable, plus allow a good current draw, but I thought I would make mine simple since he hasn't got much room inside his controller.
What proggy are you using for your schematics, Eagle, Protel etc.???