What this code means
P2199 may mean the PCM is seeing the two intake air temperature readings disagree when they are expected to be close to each other after startup.
What the vehicle may do
- The vehicle may turn on the check engine light.
- The vehicle can sometimes have little or no obvious drivability complaint.
Possible fault areas
- Possible disagreement between intake air temperature sensor readings.
- Possible loose, poor, or insecure connector and terminal contact.
- Possible concern involving IAT sensor 2.
Diagnostic path
Code overview and diagnostic direction
For P2199 on this Honda CR-V, we’re dealing with an intake air temperature correlation fault. In plain language, the PCM is comparing the two intake air temperature inputs after startup, and if the difference is significant, it treats that as abnormal. The vehicle may show a check engine light and can have little or no obvious drivability complaint. The broad areas to keep in mind are possible sensor reading disagreement, possible connector or terminal issues, and a possible concern on the IAT sensor 2 side. Start with the basic system checks and follow a structured diagnostic approach before narrowing it down.
Reproduce the operating conditions
Next, set up the conditions for the monitor. Turn the vehicle to the OFF (LOCK) mode and leave it that way for at least 6 hours. After that soak period, start the engine and let it idle for at least 10 seconds. This is the point where the PCM is looking at the intake air temperature relationship after startup.
Understand what sets the code
The logic here is straightforward: after the engine is started, if the temperature difference between IAT sensor 1 and IAT sensor 2 is significant, the PCM determines there is an abnormal correlation and stores P2199. So the diagnostic focus is not airflow volume here; it is whether those temperature inputs agree when they should.
Check the connection points
Now inspect the connector areas that can affect this comparison. Check for secure connections and loose terminals at ECT sensor 1, ECT sensor 2, the MAF sensor with IAT sensor 1, and IAT sensor 2. The expected result is that the connections and terminals are OK.
Use the inspection result to split the path
If that connector and terminal inspection is abnormal, the diagnostic path is pointing at a problem with the connections or terminals. If those connection points are normal, the path points toward a problem with IAT sensor 2. Do not guess past the inspection; let that result decide which side of the fault path you’re on.
Takeaway
Takeaway: make P2199 prove itself after the required soak, then separate connection and terminal faults from an IAT sensor 2 fault path without guessing. For more diagnostic training, visit stepdiagnostics.com.
Final check
This code often comes down to proving the temperature correlation fault under the right startup conditions, then checking the related connection points before drawing a conclusion.
For more guided automotive diagnostics, visit STEP Diagnostics.
