The switch for the check engine light on your 2002 Isuzu Rodeo can be reset by resetting the electronic control unit. The ECU controls the air-to-fuel ratio and the function of the emissions system. When these systems malfunction, the ECU will generate a fault code and the check engine light will illuminate. After fixing the emissions and replacing any sensors that need to be replaced, you need to know how to reset the switch for the check engine light.
Pull down on the fuse cover in the driver's side foot well with your fingers.
Locate the fuse for the ECU using the fuse diagram on the underside of the fuse panel.
Pull the fuse for the ECU using the fuse puller in the fuse panel.
Turn the ignition key to the "on" position.
Wait 5 minutes, then shut off the ignition and reinsert the fuse for the ECU to restore power. Then, turn on the ignition and wait for the check engine light to reset itself.