Does it still have the bail handle to hold down before you use the lever that locks the switch on after releasing the lever? Is the orange "key" covering the charge port?
if it its turning on that should mean your cable isn't broken but the interface between the handle and switch might be mis adjusted or more likely broken.
warning unsafe fix: To be honest when one broke on one of my old ones I just put a big honking switch with big cabling and replaced theres but I had that stuff on hand. that defeats safety measures though like the quick blade turnoff and if miswired could screw up the circuit board or charger!
Do a search for cmm1000 parts list on google. first few links lead to parts charts where you'll see some of the items I mentioned if you aren't already familiar with them.