CODE 37 & 43

Does anyone know exactly what these mean? The Haynes manual states a few different explanations for these. What exactly do they mean? I am having problems with it shifting into overdrive. Also for #43 it states that cylinders are misfiring. I have developed severe pinging. I have tried high octane but it doesn't help. Any help would be appreciated.

97 JGC 5.2

The '96 JGC 5.2 lists these as:

Code 37 - Transmission Temp Sensor, No Temp Rise After Start. (multiple possibilities)
- Bad Trans Temp Sensor
- No Torque convertor clutch engagement
- Open/Short in torque convertor part throttle unlock solenoid control circuit
- Park/Neutral switch stuck

Code 43 - Multiple cylinder misfires