Skip the auto shop - Our mechanics make house calls

P0112 OBD-II Trouble Code: IAT Sensor Circuit Low Input Problem

Check Engine Light

P0112 code definition

Intake Air Temperature (IAT) sensor circuit low input problem

What the P0112 code means

P0112 is the OBD-II generic code that the engine control module (ECM) has recorded the IAT sensor input below the expected sensor range.

What causes the P0112 code?

If the output voltage is less than 0.18 V for 0.5 seconds or more, the ECM determines that there is a short in the sensor circuit, and sets trouble code P0112.

What are the symptoms of the P0112 code?

  • This ECM will turn on the Check Engine Light and go into a failsafe mode.
  • The engine may be hard to start
  • A fuel mileage reduction
  • Exhaust may have black smoke out of the tailpipe on acceleration

Note: The symptoms are determined by the manufacturer failsafe ECM strategy for the vehicle during a failure and may vary between manufacturers and vehicles.

How does a mechanic diagnose the P0112 code?

  • Scans the ECM, documents the codes received, and views the freeze frame data to see the conditions present when the code was set

  • Clears the vehicle of fault codes and the retests the vehicle to see if the code comes back

  • Performs a visual inspection to see if there is a disconnected or loose electrical connector to sensor

  • Observes the sensor’s live data on the scanner while doing a wiggle test for an open circuit in wiring, connections or sensor

If no problems are noted, the mechanic performs manufacturer's specific pinpoint tests for the code and repair as needed.

Common mistakes when diagnosing the P0112 code

  • Not performing visual inspections of connections and wiring

  • Not following the manufacturer pinpoint test procedure step-by-step or skipping steps

  • Not replacing an IAT sensor only when tests indicate a problem

  • Not connecting a new or known good sensor to the harness and viewing the ECM data to see if the temperature output from the sensor is as expected

How serious is the P0112 code?

  • The P0112 code will cause the engine ECM to go into a failsafe mode.

  • The failsafe mode, depending on the manufacturer failsafe mode strategy, may cause erratic drivability symptoms.

  • Driving the vehicle for an extended time with the vehicle in failsafe mode may require additional repairs to remove carbon or repair possible ignition problems.

What repairs can fix the P0112 code?

  • Repairing or replacing the IAT connector
  • Repairing or replacing the wiring as necessary
  • Replacing the IAT with a new sensor

Additional comments for consideration regarding the P0112 code

  • The P0112 code is often associated with P0111, P0113, and P0114 codes.

  • Most intake air temperature sensor problems for code P0112 are failures from damaged or corroded harness connectors and the sensors failing internally.

Need help with a P0112 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: We changed our fuel pump

You need to have the fuel pressure regulator and injectors checked for leaking. The fuel pressure regulator is most likely leaking into the intake and causing the excessive fuel to get into the cylinders. I'd suggest getting the vehicle...

Q: p1112 code and p0112 code on the OBD2 scan tool

Hello, thank you for writing in. Both of the diagnostic troubleshooting codes that you have pulled from the computer relate to the vehicle intake air temperature sensor. The MAP sensor does play a large role in the way the vehicle...

Q: What does electrical exhaust pressure valve do and code says it's permanent

From the information I can gather on this trouble code, it looks like it is more of a general information code. There is a diagnostic flow chart that needs to be followed to identify if it is a problem with...