What it means
The intake air temperature sensor 3 circuit signal on bank 1 is above the expected range.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Intake air temperature sensor 3 on bank 1 reports air temperature to the engine control module, which uses the reading to adjust engine operation. This code sets when the bank 1 sensor 3 signal rises above the range the module expects, such as when an open signal circuit makes the reading appear unusually high.
Common causes
Most likely first.
- Signal wire open
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check-engine light on
- Reduced engine performance or power
- Poor fuel economy
How to diagnose it
- Use a scan tool to save freeze-frame data and compare bank 1 sensor 3's reading with other intake temperature readings and ambient conditions.
- With the engine off, inspect the bank 1 sensor 3 connector and harness for corrosion, loose pins, an open signal wire, or damage near hot or moving parts.
- Check whether the supply wire is pinched against battery voltage and whether the signal circuit is open, following the vehicle wiring diagram.
- With the sensor disconnected, check the signal and supply circuits for continuity, shorts, and connector contact problems.
- Test the sensor and circuit response against the manufacturer's specification before replacing any component.
Common fixes
- Repair an open or damaged bank 1 sensor 3 signal wire.
- Clean or repair corroded connector pins and restore secure terminal contact.
- Repair a supply wire pinched against a battery-positive source.
- Replace intake air temperature sensor 3 on bank 1 if it fails testing.
Can I keep driving?
If the engine runs smoothly, a short, gentle trip to a repair location is usually reasonable, but avoid hard acceleration and towing. The incorrect temperature input can reduce power and fuel economy; stop if the engine begins running poorly or warning lights indicate a more serious problem.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.