The temperature sensor and controls are a separate system from the combo switch issue you now have.

Here's what you do. Order the combo switch online. Once it's delivered, remove the lower dash on the drivers side and unplug the existing combo switch. Plug the new one in and test the functions. If it doesn't fix it, return it to the online vendor and start from square one again. If it fixes it, remove the steering wheel and replace the switch.

On my '91, I had headlights low and high beams that would not come on when turned on with the dash switch. I had parking lights functioning. I could jiggle the old combo switch and get the headlights on for 10-30 seconds at a time.

-GH

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