A/c fan speed 1&2&3 is not working only 4 ?
I had the same thing happen in my 98 Jeep GC. The Resistor that controls fan speed had burnt out. Mine was located just under the dash where the actual fan is located. It's a smallish ceramic block with a few connections that plug in. Hardest part of the job is positioning your body to see under the dash (passenger side).
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