turn signals/hazard lights not working?

What happened was, my sisters grandson, removed his old stock radio and tried to install a new after marker radio.  Instead of doing a plug and play install, he cut all of the wires off from the existing stock radio.  When he was trying to remove the stock radio, he was having such a hard time, he broke the plastic bezel that surrounds the radio.  The hazard switch is factory mounted on that bezel just above the radio.  I asked him what happened to the hazard switch that was mounted on the bezel.  He told me that he did not know what it was for and through it away with the broken bezel pieces.  So now, not only do I have a bunch of wires all cut up staring me in the face, I also don't have a hazard switch, and the turn signals don't work either.  So, I came to the conclusion that the turn signals won't work without the hazard switch plugged in because they are tied in on the same circuit.  The Toyota Dealer wants $80 for a hazard switch.  So, we end up purchasing one from a local salvage yard for $20 dollars.  I then found the wiring diagram for the radio of his car, which is a 98 Toyota Corolla at this website.  Using that wiring diagram and the one posted on the back of the new radio, I was able to match up the wire colors.  I new radio plays ok.  So the problem remains, when I activate the hazard switch, all four of the lamps on the circuit come on and stay on, including the two indicator lamps in the dash.  And the turn signals still don't work.  They don't come on at all.  I checked all of the fuses.  They are ok.  I also replaced the flasher for the hazard switch with a new one.  No change, still the same.  So, I removed the used hazard switch, and with another wiring diagram that I found on this website, I was able to identify which two wires were tied into the left and right turn signals.  So, to see if the turn signal wiring and lamps were alright,  I ran a  test wire jumper from the hot lead that feeds the hazard swtich, to the left and right turn signal leads in the wire connector individually.  Both of the turn signal indicators in the dash lit up individually, as well as the 4 lamps on the circuit.  So that tells me that the turn signal wires and lamps appear to be ok.  With that said, I'm now looking at the possibility that the used hazard swtich may be defective.  Does anyone have a wiring diagram for testing the hazard switch or have any suggestions?  Thank you, Tommy.