Code 23

What does the code 23 mean? This is for a manual, 1.0L.

You didn't post the year of your car, so I'll assume it's a OBD-1 1991-94 Model.

Diagnostic Trouble Code 23 - Intake Air Temperature (IAT) Circuit (High Voltage) . # 4 Sensor in the pic below, located on the back of the "Air Cleaner" housing.

http://i25.photobucket.com/albums/c83/MrBBody/Sensorlocationandenginewiring.gif


Complete List of 1991-1994 Geo Metro Diagnostic Trouble Codes:

Trouble Code Descriptions

DTC 12 - Normal Operating System (No Faults)
DTC 13 - Oxygen Sensor (O2S) Circuit - (Open Circuit)
DTC 14 - Engine Coolant Temperature (ECT) Circuit - (Low Temp.)
DTC 15 - Engine Coolant Temperature (ECT) Circuit - (High Temp.)
DTC 21 - Throttle Position Sensor (TPS) Circuit (High Voltage)
DTC 22 - Throttle Position Sensor (TPS) Circuit (Low Voltage)
DTC 23 - Intake Air Temperature (IAT) Circuit (High Voltage)
DTC 24 - Vehicle Speed Sensor (VSS) Circuit
DTC 25 - Intake Air Temperature (IAT) Circuit (Low Voltage)
DTC 31 - Manifold Absolute Pressure (MAP) Sensor Circuit (Low Voltage)
DTC 32 - Manifold Absolute Pressure (MAP) Sensor Circuit (High Voltage)
DTC 41 - Ignition Control (IC) Circuit Error
DTC 42 - Camshaft Position (CMP) Sensor (No Signal For 2 Seconds)
DTC 46 - Idle Speed Control Motor Circuit (Upgraded Emissions Only)
DTC 51 - Exhaust Gas Recirculation (EGR) Circuit