[AllanC]

You need to find the fuse box for the vehicle. It should be in or around or under the dash area. If you have an owner's manual it should indicate its location. Check the fuse for the backup lamps and make sure it is good.

Unplug the wire connector bundle at the transmission range selector. Locate the 12 volt power feed white wire in the connector. Use a volt ohm meter and check for 12 volt power on the white wire with the ignition switch in the ON / RUN position. If no power trace the wire back to the fuse box and look for shorts or breaks.

If there is 12 volt power at the white wire fashion a short jumper wire and connect to the wire terminal with the violet wire / black tracer. With the ignition switch in the ON / RUN position, the backup lamps should illuminate. If they do not shine, then check the black ground wire for continuity to ground at each backup lamp socket.

 

[AllanC]

Do you have a factor service manual? If yes there are pictures in section 8 wiring that show how wiring is routed in the engine compartment.

I have a service manual for a 2003 Neon. It shows the switched, fused ignition output circuit uses fuse #7 for the backup lamps, power driver window switch, compass / temperature display in mirror and rear window defogger. It is possible that the PT Cruise could be wired similarly. Are any of these electrical accessories not functioning in your vehicle?

You might look for a large bundle of wires in the lower left side of engine compartment. There would have to be an electrical connector to pass the circuity from the interior cabin and instrument panel into the engine compartment. Maybe that is loose or dirty or corroded. The ignition RUN circuit would have to be in those bundle of wires.