With a scan tool.
With a scan tool.
You need to have a diagnostic meter to read the codes, then book to tell you what they mean.
A code reader or scan tool is required.
with a scan tool, 97 neons are OBDII so they will talk directly to the scan tool. try a parts house has most will read codes for free
P0420 is catalytic converter efficiency failure.
Diagnostic codes are generated by your on-board computer. They tell you what problems the computer has identified with your engine. The codes are numbers. The code numbers are read by an instrument that plugs into a special jack under the dash. Auto parts stores often will check your diagnostic codes for free, or you can have your dealer do it.
It could, have the codes read.It could, have the codes read.
The codes are read with an OBD2 scanner.
Have the codes read, and fix the cause. May be the rear axle speed sensor.
That requires a scan tool.
This could be one of a thousand things, you have to read the codes and go from there. Switch ignition on (not start) three times quickly in a row, and see what appears in the odometer window.
autozone will do it for you for free.