You may need to replace the heater\ac control switch, it may be stuck in the off position which would prevent the blower and the ac compressor from turning on.
It is either the fuse or relay. also check the heater/ ac control switch.
A bad alternator will cause the fan blower not to work properly. Have the alternator tested!
To wear....
what might cause the engine on a 2000 Isuzu rodeo to burn oil 1/2 quart of oil every 300 miles
Some causes for a 1999 Isuzu Rodeo to stop running include a lack of fuel, a bad battery, or defective spark plugs. There can also be a combination of issues which would need to be diagnosed by a mechanic.
they all lose oil dont fix it cause you cant it will always leak
Cause the battery to explode or damage the electrical system in the car.
Trouble code P0401 means:Exhaust gas recirculation flow insufficient detected
Check the belt on your alternator. If it is not tight enough it will squeal on a Rodeo. Be sure to get it checked soon or your belt could fall off or burn up your alternator and then you are stuck!!
either a fuse blown low freon pressure or pressure switch bad to test take two wire plug off of evaporator and jump wires see if compressor kicks in
you have lost your oil cap
DTC P1125: ELECTRIC THROTTLE CONTROL (ETC) LIMIT PERFORMANCE MODE.