DTC P0110: Intake Air Temperature (IAT) Sensor Circuit Malfunction

NOTE: IAT sensor is built into Volume Airflow (VAF) sensor. For DTC P0110 test purposes, VAF sensor will be referred to as IAT sensor. For terminal identification, see VAF sensor under TERMINAL IDENTIFICATION . For circuit and wire color identification, see WIRING DIAGRAMS article.

Using a thermometer, check engine compartment ambient temperature. Using scan tool, read IAT sensor temperature (item 13). Compare both readings. If readings are not about the same, go to next step. If readings are about the same, fault is intermittent. See INTERMITTENT DTCS .
Disconnect IAT sensor connector. Using DVOM, check resistance between IAT sensor terminals No. 5 and 6. Resistance should be 2300-3000 ohms at 68°F (20°C) or 300-420 ohms at 176°F (80°C). Using a hair dryer, warm IAT sensor while monitoring DVOM. Resistance should decrease evenly as temperature rises. If resistance is as specified, go to next step. If resistance is not as specified, go to step 6).
Turn ignition on. Using DVOM, check voltage between ground and IAT sensor connector terminal No. 6. Voltage should be 4.5-4.9 volts. Turn ignition off. Using DVOM, check for continuity between ground and IAT sensor connector terminal No. 5. Continuity should exist. If voltage is as specified and continuity exists, go to next step. If voltage is not as specified or continuity does not exist, repair or replace IAT sensor connector. Go to step 6).
Inspect connectors and wiring harness between IAT sensor and PCM. Repair as necessary. Go to step 6). If connectors and wiring harness are okay, go to next step.
Inspect PCM connector for damage. Repair or replace connector as necessary. Go to next step. If connector is okay, replace PCM. Go to next step.
Road test vehicle and attempt to duplicate conditions that caused original complaint. Recheck for DTCs. If no DTCs are displayed, test is complete.