P00DA

Code

Generic P — Powertrain

Ambient Air Temperature Sensor Circuit B Range/Performance

Brand: Generic

Type: P — Powertrain

Views: UK: 19 EN: 36 RU: 29

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or short in sensor wiring (to ground or to reference voltage)
Corroded/damaged sensor connector or pins
Failed ambient air temperature sensor (thermistor)
Water intrusion or contamination at sensor or connector
Incorrect or missing reference voltage/pull-up from PCM
Intermittent harness fault (chafe, broken strand, poor repair)

Symptoms

MIL/Check Engine light illuminated
Ambient outside temperature reading incorrect or not displayed on dash/infotainment
HVAC/climate control behavior abnormal (e.g., incorrect automatic mode decisions)
Cold/hot start or engine management adjustments may be affected (minor)
Fault may be intermittent depending on wiring movement or moisture

What to check

Read freeze frame and related stored data with a scan tool; confirm P00DA and any related codes
Visual inspection of sensor, connector, and wiring for corrosion, damage, or water entry
Wiggle test wiring while monitoring live AAT data for intermittent changes
Measure connector/reference voltage at sensor with ignition ON (key ON, engine OFF)
Measure sensor resistance across terminals at known ambient temperature and compare to expected
Back-probe signal wire at PCM to confirm the signal arrives and is within expected range

Signal parameters

Sensor type: typically an NTC thermistor (resistance decreases as temperature increases)
Typical PCM input voltage range: about 0.1 V to 4.9 V depending on ambient temperature and vehicle design
Typical resistance range (approximate, varies by sensor): on the order of 100 kΩ at very low temps down to ~1 kΩ at high temps; consult OEM spec for exact values
Operating ambient temperature range: commonly -40°C to +85°C or up to +125°C depending on sensor
If reference is a pull-up to 5 V, short to 5 V will read high voltage; short to ground will read low/no voltage

Diagnostic algorithm

Verify code and vehicle conditions: Purchase or use a scan tool to confirm P00DA, note freeze frame, monitor live AAT_B value and compare to actual ambient temperature.
Visual inspection: With ignition off, inspect the sensor, mounting, and connector for corrosion, bent pins, broken locking tabs, moisture, or physical damage. Repair or reseat as needed.
Check reference and signal voltages: With key ON (engine OFF) back-probe the sensor connector. Confirm the reference/pull-up voltage from PCM and the signal voltage are within expected ranges (see vehicle service manual).
Measure sensor resistance: Disconnect sensor and measure resistance across sensor terminals at ambient temperature. Compare to OEM spec or to a known-good sensor. Resistance should change when warmed/cooled (breath test or use ice/warm water carefully).
Inspect wiring continuity: With sensor disconnected, check continuity between sensor connector and PCM input pin. Also check for short to ground and short to battery voltage.
Repair wiring/connectors: Repair broken wires, corroded terminals, or connector issues. Use dielectric grease for moisture-prone connectors after repair.
Replace sensor if out of specification: If wiring and reference voltages are correct but sensor resistance/voltage is outside spec, replace the AAT sensor with OEM or correct-spec part.
Re-scan and verify: Clear codes, perform a key cycle and road/ambient test to confirm proper operation of AAT_B signal and that P00DA does not return.
If code returns after sensor/wiring verified: consider PCM input fault or intermittent harness condition. Consult manufacturer procedures for PCM tests or dealer-level diagnostics.

Likely causes

Water-corroded or loose connector at AAT sensor
Broken or shorted wire between sensor and PCM
Failed thermistor inside AAT sensor
Aftermarket sensor or incorrect replacement with different characteristics
Poor ground or missing reference/pull-up in harness

Fault status

⚠️ Status

Ambient Air Temperature Sensor Circuit B reading out of expected range or not responding correctly. Check sensor, connector, wiring, reference voltage and PCM input; repair or replace faulty components and clear the code.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours