My boyfriend recently bought a 2003 G35 sedan and earlier today it decided not to start. It cranks, turn over then shuts off, the horn constantly stays on for about a minute and sometimes when he tries, the lights turn on, then they dont. He tried checking for the ECU relay cant find it, and the IGNITION relay is functional. Anyone else have problems like this happen to them?

 

ouch. does it do this when cold or no? there are ipdm e/r issues in cold temps. and with miles, the cam sensors will go out. just replaced one in a 04 sedan today. lol. able to check for any codes if the SES light is on?