Duane Covert

My 2003 911 Cab has been running great, until recently. Was running errands, everything fine. Last errand done, upon starting, I saw 2 warning lights - airbag and rollover protection. Car running fine, got home without incident. When I tried to start it later to troubleshoot, I got nothing (except ;those same 2 lights). Silence. I knew the battery was old, so I replaced it. Same symptoms. Towed to local Porsche expert, and he is puzzled too, although he thought it was a faulty ignition contact - nope. Diagnosis compounded by my aftermarket stereo and Viper alarm system. Suspecting an alarm malfunction (has been operating fine) but not smart enough to go beyond that. Initial indication was those 2 darned warning lights. Any thoughts from the experts? Thank you in advance.

DBJoe996

The airbag and rollover lights do not go off on their own. They have to be turned off with Durametric or at the Porsche dealer, or an Indy with a really good OBDII reader. Query the DME/ECU for any codes, then reset/turn off the warning lights. See if they come back. All manner of quirky issues arise when battery voltage is very low. Not an alarm issue IMHO.

Duane Covert

DBJoe996, thanks very much for your input. I'm passing along to our resident expert who has all the diagnostic tools. Will post more if this does the trick!

dporto

Check your chassis grounds - especially the Y cable and the little cable by the rear passenger side wheel (runs from the engine block at the end of bank 2 cam cover to the chassis). Clean them up good, and tighten to spec. Good luck

JTT

Replace the ignition switch. It's a cheap part, and causes all sort of weird codes and issues. I had similar issues with mine , lights flashing on, intermittent, then no starting. Replaced $15 switch, all good. Part #4A0 905 849 B. You can pick one up at Napa (cheap one, good enough to test) or at Audit dealer for about double the price.

Duane Covert

Thanks very much to all who jumped in to help. My Porsche expert, after much searching, found and replaced a frayed wire under the back seat. The car now starts. I haven't picked it up yet so I can't give details, but I certainly will so maybe others can learn.