Canon Speedlite 155A Fix

[verbatimium]

I recently bought a Canon film camera with a Canon Speedlite 155A flash. The Flash is very clean, no corrosion in the battery compartment. I put the batteries in the flash, and when I turn it in, I can hear the flash charging. However, I cannot get it to manually fire, or fire when on the camera. Anyone know what the problem could be and how to fix it? Do the bulbs ever burn out? I have never came across a flash in this state before where you hear it charging up but it cannot be fired.