After checking everything mentioned in the previous post, and checking all connections (at the battery, at the chassis grounds, at the starter, etc.) and if all checks o.k., you might also check the neutral safety switch. Good luck.

__________________
Mike

2000 SL500 22,000 miles
1981 300CD 188,000 miles
1979 450 SEL 266,000 miles
2005 Cadillac CTS 25,000 miles