How is fault code P0111 fixed?

A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training. 1. Plug in a scanner and look at the live IAT reading with the engine stone cold. It should sit within a couple of degrees of ambient and match the coolant temp on an overnight-cold car. If it's miles off or barely moves, you've found your problem 2. Pull the connector and inspect the pins for green corrosion, oil, or a loose fit. Wiggle the loom while watching live data to see if the figure jumps about 3. Have a proper look at the sensor element for carbon or oil film, give it a clean with MAF cleaner and recheck 4. Watch the IAT climb as the engine warms and you drive. A healthy sensor responds smoothly. A lazy one lags or sticks 5. Check the intake ducting and clips for splits or a loose jubilee clip letting hot underbonnet air in 6. Measure sensor resistance cold and warm with a multimeter against the figures in the manual if you've still not pinned it down

Intake Air Temperature Circuit Range/Performance Problem

Jump to the fix

Severity

Medium

Can I keep driving?

Usually drivable, but get it diagnosed without delay.

First step

A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training. 1. Plug in a scanner and look at the live IAT reading with the engine stone cold. It should sit within a couple of degrees of ambient and match the coolant temp on an overnight-cold car. If it's miles off or barely moves, you've found your problem 2.

PPowertrain
0Generic code
1Fuel / Air
11Sequence number

What does it mean?

The P0111 occurs when the PCM reads a signal in the IAT circuit which varies from expected values based on other sensor readings (such as the Engine Coolant Temperature sensor). This is a distinct condition from related codes P0112 and P0113. For these codes the PCM reads either a consistent high or low voltage in the IAT circuit. See the IAT in depth article (P0112) for more background on the IAT sensor.

Note: A Range/Performance related code will be set when either a sensor or other component does not perform within the range the PCM (Powertrain Control Module) expects to see, given the current engine load/speed, and information gathered from other sensors.

The possible causes of Range/Performance codes are likely to be defective sensors as easily as they are likely to be the result of wiring issues that affect the operation of the affected sensor or component, which means that with these codes, it is important to regard all sensors and components as part of the control circuit the code refers to.

Symptoms

Likely causes

How to fix it

Codes From the Same System

All Fault Codes

Related Similar Codes

This information follows the generic OBD-II definition and does not replace a vehicle-specific diagnosis. The severity rating is rule-based; an authorised diagnostic reading is required for a definitive answer.