Automatic trans? Might be the Neutral Safety Switch. Try wiggling the shifter when this happens.
Got gauges? Read the voltmter when the switch is in the On position. What's the meter do when you go to Start? Does it drop? If so, you've got starter/battery connection issues. If not, most likely NSS problems.
Originally Posted by chris87xj
If you own a Renix Jeep, you'll want to check this out. >
An index to over 25 write-ups can be found in Post #1.
Cruiser's Mostly Renix Tips