Those codes are for petrol injector circuits 1 through 4 and evap purge control solenoid open circuit respectively, they could all have been caused by blown pump pump fuse and/or blown pump relay if same fuse/relay sends 12v to the engine loom and fuel pump.
If you now measure the fuel pump electrical resistance and it's not shorted, the jury will be out as to whether you just paid for changing your fuel pump unnecessarily. There is the chance that if pump resistance is normal, which may be a couple of ohms, it could still have been broken and not working.... Engine shouldn't start at all if you disconnect the LPG ECU, LPG ECU wouldn't disable the evap purge valve but removing Aldesa ECU could potentially effect a fix if the ECU had crashed somehow and Aldesa has that built in immobiliser facility (could have crashed and turned on it's built in immobiliser). I'd be connecting my old pump up to a battery to see if it works and if it does would have to wonder if swapping a fuse/relay or just temporarily disconnecting the LPG ECU was the real fix
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