Propane generators, like most remote propane appliances, have a solenoid operated valve to open and close and allow the propane to flow. The "Start" signal opens that valve while starting but then it needs a "running" signal from the controller to continue running. Since it starts but then shuts off after a few seconds I'd be looking at that solenoid to see if it is closing and causing the shutdown: if so, find out why it is not getting the "run" signal.
Ted & Melinda
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