The fault code 32 is officially titled "low cranking speed". The speed is read from generator stator windings. If your set sounds like it is cranking over at normal speed, then the problem is most likely a failed generator stator or control board (part of inverter/controller assembly)
very difficult to diagnose exact problem, without equipment. Fault code 33 (high coolant temp) is much more consistent with your symptoms, i.e. running for short time then shutting down. causes are water pump belt broken or slipping, low coolant level (check at rad cap, not just looking at overflow bottle), or faulty coolant temp sending unit.