I have read that when you have a fault and you fix it, the ECU has to make so many cycles before it resets it's counter. It was either 10 or maybe 50 starts. Since you had no issue before your battery took a hike then we can rule out an oil pressure problem. I have a 2000S and I will turn on my key and I watch the oil gauge cycle...and it really takes about 30 seconds before it stops. Now the only thing I think it could be, you fried the sending unit, maybe. Let us know watch you find. Little things like drives me to drink another beer.
