Applicable Systems
OBD-II
Symptoms
IAT sensor signal out of range; ECM cannot compensate for intake air temperature; may cause hard starting.
Possible Causes
- IAT sensor open or short circuit
- Sensor connector corrosion
- IAT sensor internal thermistor failure
Troubleshooting Steps
- Step 1: Check IAT sensor resistance vs temperature chart
Resistance matches chart - Step 2: Inspect IAT sensor connector
Connector clean and tight - Step 3: Check signal wire continuity
Wire continuity good - Step 4: Replace IAT sensor if resistance out of spec
New sensor resistance matches chart - Step 5: Clear code and verify IAT reading
IAT reading matches ambient temp
How to Reset
Clear with OBD-II scanner after sensor replacement.
Common Replacement Parts
- IAT Sensor (OEM spec)
Frequently Asked Questions
- Q: Where is IAT sensor located?
Usually in air intake tube between air filter box and throttle body, or integrated with MAF sensor assembly.
Source: SAE J2012 standard DTC list + OBD-II portal
Category: OBD-II