Hi guys
First off I would like to thank everyone who have contribute information on this web page…

Well were do I start? 99 STS..great car BUT I am currently frustrated with a intermediate stalling problem.
Problem engine cranks but fails to start, when this occurs my dash is completely blank
No lights or gauges, no icons i.e. airbag/engine light completely blank, but all else is fine radio/heater/seat/doorlocks blah blah blah. I must wait until my dash lights up to restart or start the engine. Sometime when I crank the engine (after it stalled or when I getting ready to leave) only the engine icon light appears while cranking no other lights, but when this happens the engine will Fire and stall immediately. I must wait until the whole dash light up to start the engine. This problem is getting worse but no enough to be properly diagnose
When this happens I sometimes call my wife over for her to crank the engine while I check for spark or fuel pressure but never get a chance the engine starts like nothing was wrong. NO CODES are ever present; I have currently changed all relays in the fuses box, and the PCM to no avail. Just recently the service suspension sys message is on



My wife will no longer drive it due to the dangerous situation it caused when it stall
On her when exiting the highway losing the power steering is some scary

Help

I also have the same problem on my 99 STS. The car usually wont start unless it is jump started for some reason. The battery is holding a charge, all the connections are good but it will not start. Some times the dash comes on and sometimes it wont. Sometimes the car dies immediately and sometimes while cruising down the road. The only time it starts is when the dash comes on and I hear the dings of the bell. I have watched the voltage monitor on the dash and sometimes it will drop to 7.5 volts but I still have about 14 at the battery and under the hood when checking with a meter. Sometimes the AC wont kick on right away either. I have also noticed when trying to start the car that I cannot scroll through the info on the dash.

Both of ya- battery checks out, connections ok and no codes? My next step would be a starter draw test. Your ignition keys are in good shape- not worn out?

Update- I read too quickly, and didn't get it all. Is your alternator outputting as it should? I think it's about 10.4-5V and things start shutting down. All those computers and modules take an ungodly amount of power to run.