Hobart lx30 : rinse cycle

If it clicked then sou ds like the door read switch is ok. Does it do nothing for about 2 or 3 minutes then carries out a rinse? If so this sounds like the wash pump and or the wash pump relay on the pcb.

Can you describe the sequence of operation?
Fill ok?
Booster or tank heating ok?
wash pump running ok?

I found this website that can help you further.
Hobart Kitchen Appliance Product Support ManualsOnline com

Check the rinse pump. The tubing needs to come from the supply into the bottom of the pump, and the pump should be running clockwise. If the pump tube is worn, the rinse pressure will blow through the pump filling the bottle

What type of detergent is not necessarily important - anything intented for use in commercial dishwashers should be sufficient. A restaurant supply store should have something suitable for you.
Also, in case you don't already know, the LX30C is the non-booster-heater version of the LX30 (LX30H has a booster heater). Without a booster heater, you'll need to use chemical sanitizer. The LX30C should, hopefully, have a sanitizer pump installed to inject chemical sanitizer into the rinsewater stream. Most of these dishwashers also have a detergent pump to inject detergent into the wash tank and rinse aid pump for chemical rinse aid.
If present, these pumps are located in the bottom of the machine. Remove the lower front panel (2 screws) and look for the small, black plastic assemblies with 2 hoses connected to each.

Check that your supply faucet is open, Check if there is a screen in the supply line, these can become blocked due to scale deposits from the mains. If there is no screen check that the inlet solenoid valve has not got blocked. If none of the above help, check that there is power getting to the solenoid valve when the machine is supposed to be on the fill cycle. If no power is getting to the valve, the timer might be faulty. (You can try hand filling the machine and see if it goes through a cycle, at least up to the rinse stage, this will tell you if the timer control is working).

same pump does both, are you certain there is nothing in front of the pump? I would pull the safety hood off and look inside

you have to go into program and activate the detergent pump.sounds like somebody deativated the det. program

it supposed to work throgh the washing cycle,therefore you better trace,and inspect the line of the detergent,maybe it'stuck somewhere,and if it's ok check the panel board.does the pump receive voltage through the washing cycle.

the pump shouldn't turn on when the rinse cycle is on - it uses only fresh water straight from the water line - after the wash cycle is over - wait 5 seconds, then open the doors and see if there is any rinse coming out of the rinse arms.
If only a little is coming out - check the rinse arm spray jets to see if there is debris caught in them -
if no water is coming out - it could be a faulty rinse solenoid