Engine Intake Air Temperature (IAT) Sensor 1
The Engine Intake Air Temperature sensor is reporting a fault.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The IAT sensor, which measures how hot the air entering the engine is, is sending back a reading that's out of what's expected. For example, if the air temperature is actually 80°F but the sensor says it's 175°F, there’s a problem.
What the computer is actually seeing
The engine control module (ECM) expects a range of input from the IAT sensor that usually varies between -40°F to 215°F (-40°C to 102°C). If the reading goes outside this range or is inconsistent, it triggers a fault code.
What a healthy reading looks like
IAT sensor should read within -40°F to 215°F. Resistance for a good sensor typically ranges from 3,000 ohms at -40°F to 200 ohms at 212°F.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the IAT sensor wiring and connectors for damage or corrosion. Check for any pinched wires or shorts. Decision: If damage is found, repair as needed. If no damage, proceed to Step 2.
- 22. Measure the resistance of the IAT sensor at operating temperature (around 80°F or 27°C). Compare it to expected values (should be around 1,500 ohms). Decision: If resistance is within spec, proceed to Step 3. If not, replace the IAT sensor.
- 33. Check for any intake air leaks between the air filter and the engine. Pressure test if necessary. Decision: If leaks are present, repair and retest. If none, proceed to Step 4.
- 44. Clear the fault code and run the engine to monitor IAT readings with a scan tool. Decision: If code returns, replace the IAT sensor. If it does not return, confirm repairs were effective.
Common causes
- Wiring harness issues (shorts, opens, or damage)
- Faulty intake air temperature sensor
- Poor connection at the sensor plug
- Air leaks before the IAT sensor
- Contaminated sensor connector
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
It's generally drivable, but performance may be degraded, and fuel mileage could suffer. Fix it soon to avoid running into bigger issues.
Will this code come back after repairs?
If all issues have been resolved properly, it should not return. If it does, further diagnosis is needed.
Why is this code paired with SPN 1102?
SPN 1102 often indicates a range fault with the IAT sensor, suggesting the sensor or its wiring may have similar issues.
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