How do you fix ecm code 23 on 1995 Geo Metro?

ECM code 23 on a 1995 Geo Metro indicates an issue with the intake air temperature (IAT) sensor. To fix this, first, check the wiring and connections to the IAT sensor for any damage or corrosion. If the wiring is intact, test the sensor itself for proper resistance; if it's faulty, replace the IAT sensor. Once repairs are made, clear the ECM codes and test drive the vehicle to ensure the issue is resolved.