Chrysler Repair: 2004 300M: fault code readout by ignition switch?, 4 digit numbers, autoparts store

Question
can I retrieve ecu codes without a scanner o a 2004 300M

Answer
Hi Wayne,
Try the ignition key: "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see the mileage reading change to show any 4 digit numbers preceded by P.
Let me know what you get. If nothing shows up, then a plug-in reader is needed. You can often get a free readout at a nationwide autoparts store such as Autozone.
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Thanks,
Roland