1994 Plymouth Voyager Just quit

To determine if its a fuel or ignition problem do below then comeback

Get a carb cleaner and spray into the carb or the throttle body on an EFI. Did it start and die? If not disconnect a sparkplug wire or 2 and ground it to the engine -have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel problem, check the fuel pressure to rule out the fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light.

Fuel pump/Pressure Regulator and Injector/s checks out-start checking the ignition system-power to coil, coil/s itself, distributor pick-up, control module, Cam and Crankshaft sensors.

If both fuel and spark is present-check the valve and ignition timing, this will lead you to problems with compression and valves opening and closing at the wrong time

I believe the code 55 indicates end of codes.

Code 12 indicates - Direct Battery input to PCM disconnected within last 50 ignition key-on cycles. Normal if battery has been disconnected, otherwise check battery power and ground connections.

And Code 37 - Torque converter clutch
solenoid CKT or Trans temp sensor too high or low

OK - The not starting when was the last time you had a tune-up? Cap, Rotor and Plugs?