P00AD - Intake Air Temperature Sensor 1 Circuit High Bank 2
Last updated:
System
Powertrain (Engine & Gearbox)
Related Fault Codes
Technical Description
The P00AD diagnostic trouble code (DTC) indicates that the Engine Control Module (ECM) has detected a voltage signal from the Intake Air Temperature (IAT) sensor 1 on Bank 2 that is higher than the maximum calibrated limit. The IAT sensor is an NTC thermistor; as temperature increases, resistance decreases. A 'Circuit High' condition typically signals an open circuit, where the ECM sees the full 5V reference voltage because there is no path to ground through the sensor. Bank 2 refers to the bank of the engine that does not contain cylinder #1. This input is critical for the ECM to calculate air density, fuel trim, and ignition timing.
Possible Causes
Faulty Intake Air Temperature (IAT) sensor (internal open circuit)
Poor connection or oxidized terminals at the sensor plug
Wiring break in the signal or ground circuit leading to the sensor
Faulty Engine Control Module (ECM) failing to interpret the signal
Symptoms
Recommended Solution
- Visual Inspection: Check wiring and the connector for IAT sensor 2 (Bank 2). Look for frayed wires or corrosion.
- Voltage Test: Disconnect the sensor. With ignition ON, check for a 5V reference signal and a solid ground connection.
- Resistance Test: Measure the sensor resistance (Ohms). At 68°F (20°C), it should typically be between 2000-3000 Ohms. If it reads O.L (open loop), the sensor is faulty.
- Live Data: Use a scan tool to monitor IAT Bank 2 temp. If it reads -40°F/C, the circuit is open.
- Component Replacement: Replace the IAT sensor if electrical values are out of spec.
Mechanic's Tip
Before replacing expensive components, always double-check wiring and connections. 80% of all sensor faults are actually due to corroded contacts or broken wires.
Do you also have
other fault codes?
See how P00AD connects with your other fault codes. Our advanced analysis tool identifies causal relationships and root causes directly.