Pop off the plenuim? chamber cover (cover between battery and fuse box) Get sombody to operate the heater slider in the car. Where the heater matrix is, there should be a blue tube coming out of the bulkhead. This will have a Wire/rod coming out of it and onto the heater valve. This works simular to a throttle cable sort of thing. Im guessing either the gay little clip has come off that fixes the rod to to valve. But could be a snapped rod, broken valve, or somthing amiss with the internal control side.