P0112
Fix within 1-2 weeksThe engine computer detects a very low voltage signal from the Intake Air Temperature (IAT) sensor, indicating the air entering the engine is extremely cold or there's an electrical fault.
Code P0112 means your Intake Air Temperature sensor is sending a low voltage signal. Common causes: Faulty IAT sensor (60%), wiring issues (35%). Drivability: Yes, safe to drive, but fix soon. Repair cost: $20-$80 DIY, $70-$305 professional.
Can I Drive With P0112?
Yes, safe to drive
No restrictions
Stop driving immediately if: Flashing CEL, loud noises, burning smell, rotten egg smell, significant power loss
Symptoms of P0112
- 1Check Engine Light is on
- 2Rough idle or stalling
- 3Reduced engine power
- 4Poor fuel economy
- 5Hard starting, especially when cold
- 6Black smoke from the exhaust
Common Causes of P0112
Parts most likely causing this code, ranked by probability
The IAT sensor itself has failed internally and is sending an incorrect low voltage signal to the engine computer.
60% of P0112 cases are fixed by replacing the IAT sensor
Damaged, corroded, or shorted wiring in the IAT sensor circuit, or a loose/corroded connector, causes the low voltage reading.
35% of P0112 cases are fixed by repairing wiring or connector issues
A rare internal fault within the engine computer can incorrectly interpret or process the IAT sensor signal.
5% of P0112 cases are fixed by replacing the ECM/PCM
Check These First (Before Buying Parts)
- Visually inspect the IAT sensor and its electrical connector for any obvious damage, corrosion, or loose connections.
- If the IAT sensor is integrated with the MAF sensor, try cleaning the MAF sensor with a specialized MAF cleaner spray.
How to Diagnose P0112
- 1Visually inspect the IAT sensor and its electrical connector for damage, corrosion, or loose connections.
- 2Using a multimeter, check the resistance of the IAT sensor at various temperatures (if accessible) or check the voltage signal with the engine running.
- 3Inspect the wiring harness leading to the IAT sensor for any signs of fraying, cuts, or shorts to ground.
- 4If the IAT sensor is integrated into the Mass Air Flow (MAF) sensor, clean the MAF sensor with specialized cleaner.
- 5If all other checks are inconclusive, test the continuity of the IAT sensor circuit back to the engine computer.
P0112 on Popular Vehicles
Toyota Camry
2007-2024On many Camry models, the IAT sensor is a separate component or integrated into the MAF sensor. A P0112 often points directly to a faulty IAT sensor or MAF sensor.
85% fixed by IAT/MAF sensor replacement or wiring repair
Honda Accord
2003-2024Honda Accords commonly experience IAT sensor failures, which can be a standalone sensor or part of the MAF. Check the sensor and its harness for damage.
80% fixed by IAT/MAF sensor replacement or wiring repair
Ford F-150
2004-2024For many F-150 trucks, the IAT sensor is built into the Mass Air Flow (MAF) sensor. A P0112 often requires replacing the entire MAF sensor assembly or cleaning it.
75% fixed by MAF sensor replacement or wiring repair
Frequently Asked Questions
What does P0112 mean?
P0112 indicates that the engine's computer is receiving a voltage signal from the Intake Air Temperature (IAT) sensor that is too low. This signal suggests the air entering the engine is extremely cold, or there is an electrical problem in the sensor circuit.
Can I drive with P0112?
Yes, you can drive safely with a P0112 code, but you should fix it within 1-2 weeks. The engine computer will use a default value for air temperature, which can lead to reduced fuel economy, poor performance, and increased emissions.
Will P0112 clear itself?
No, P0112 will not clear itself. The engine computer stores this code until the underlying fault is repaired and the code is manually cleared with a scan tool, or after several drive cycles without the fault present.
How do I fix P0112 myself?
Start by visually inspecting the IAT sensor and its connector for damage. If the sensor looks fine, test its resistance with a multimeter. If the sensor is faulty, replace it. If the wiring is damaged, repair it. If the IAT is part of the MAF sensor, try cleaning the MAF sensor first.
How much does it cost to fix P0112?
The cost to fix P0112 ranges from $20-$80 for DIY parts. A professional repair at a shop will cost $70-$305, including parts and labor.
P0112 keeps coming back - why?
If P0112 keeps returning, it means the initial repair did not address the root cause. This often points to an intermittent wiring issue, a faulty connector that wasn't fully repaired, or a rare engine computer problem that was overlooked.
Will P0112 fail emissions/smog test?
Yes, P0112 will cause your vehicle to fail an emissions or smog test. The Check Engine Light being on automatically results in a failure, and the code itself indicates an issue with engine management that affects emissions.
What's the difference between P0112 and P0113?
P0112 indicates a 'low input' from the IAT sensor, meaning the voltage signal is too low (suggesting extremely cold air or a short). P0113 indicates a 'high input', meaning the voltage signal is too high (suggesting extremely hot air or an open circuit).
P0112 on Ford F-150?
On many Ford F-150 models, the IAT sensor is integrated into the Mass Air Flow (MAF) sensor. If you have a P0112 on an F-150, you will likely be replacing the entire MAF sensor assembly, or at least cleaning it thoroughly, as the IAT is not a separate component.
Questions to Ask Your Mechanic
Did you check the IAT sensor's live data readings with a scan tool to confirm the low voltage?
Good answer: Yes, the live data showed a consistent reading of -40°F (-40°C) even when the engine was warm, confirming the low input.
Have you inspected the IAT sensor's wiring harness for any signs of a short to ground?
Good answer: Yes, I performed a continuity test and checked for shorts to ground on both wires leading to the sensor. The circuit is intact and not shorted.
Repair Cost Estimate
DIY Repair
Parts only
$20-$80
Shop Repair
Parts + labor
$70-$305
Save $50-$225 by doing it yourself
Difficulty
beginner
Time
0.5-1 hours
Beginner-friendly - replacing an IAT sensor typically involves simple hand tools and is a good entry-level DIY repair.
Cost of Waiting
Ignoring P0112 leads to the engine running with incorrect fuel mixtures, causing poor fuel economy and increased emissions. Over time, this can lead to premature failure of expensive components like your catalytic converter ($800-$2,500 replacement) due to unburned fuel.
While You're In There...
If you're accessing the intake system to replace the IAT sensor, it's a good time to check and replace the air filter if it's dirty, as it affects air flow and sensor readings.
If your IAT sensor is integrated into the MAF sensor, cleaning the MAF sensor can often resolve the issue without full replacement.
Tools You'll Need
- Basic hand tools (screwdriver, wrench)
- Multimeter (for testing sensor resistance/voltage)
- OBD-II scan tool (to confirm code and clear it)
P0112 is a common sensor code that is usually straightforward to diagnose and fix. Most repairs are inexpensive and your engine will run much better afterward.
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Your Next Steps
Step 1: Visually inspect the IAT sensor and its electrical connector. Look for frayed wires, corrosion, or a loose connection. Repair any obvious damage.
Step 2: If the visual inspection doesn't reveal the problem, use a multimeter to test the IAT sensor's resistance or voltage output. Compare readings to your vehicle's specifications.
Step 3: If the sensor tests bad, replace the Intake Air Temperature sensor. If your IAT is part of the MAF sensor, you will replace the MAF sensor. Clear the code with an OBD-II scan tool.