What Does P00A3 Mean?
The PCM has detected that the charge air cooler temperature sensor circuit on bank 2 is reading above the maximum expected voltage threshold, indicating a high-circuit condition. For an NTC thermistor sensor, this means the circuit has very high resistance (open circuit or disconnected sensor), causing the PCM to see an implausibly low temperature reading. The PCM will substitute a default value and may not properly regulate boost pressure or fuel delivery on bank 2.
Common Causes
30%
Open circuit in the charge air cooler temperature sensor (failed sensor element)
25%
Disconnected or loose sensor connector on bank 2 CAC temperature sensor
25%
Broken wire in the signal or ground circuit between the sensor and PCM
12%
Corroded connector pins creating an open-circuit condition
8%
Signal wire shorted to the 5V reference circuit
Diagnostic Steps
1
Check the bank 2 CAC temperature PID — a reading of -40°F or an implausibly low temperature on a cold engine confirms a high-circuit (open) condition.
2
Inspect the CAC temperature sensor connector on bank 2 — verify it is fully seated, the locking tab is engaged, and the connector is not cracked or broken.
3
Disconnect the sensor and measure resistance across the sensor terminals (typically 2–3 kΩ at 68°F/20°C). An OL reading confirms a failed sensor element.
4
If the sensor tests good, use a jumper wire to connect a known-good resistor (e.g., 2.2 kΩ) across the harness-side connector pins — the PID should show a plausible temperature, confirming wiring integrity back to the PCM.
5
Check for breaks in the signal and ground wires by performing continuity tests from the sensor connector back to the respective PCM pins.
Estimated Repair Cost
$50 - $250
Parts + labor, varies by vehicle and location
The PCM has detected that the charge air cooler temperature sensor circuit on bank 2 is reading above the maximum expected voltage threshold, indicating a high-circuit condition. For an NTC thermistor sensor, this means the circuit has very high resistance (open circuit or disconnected sensor), caus...
The most common cause of P00A3 (Charge Air Cooler Temperature Sensor Circuit High Bank 2) is: Open circuit in the charge air cooler temperature sensor (failed sensor element)
Typical repair costs for P00A3 range from $50 to $250, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Driving is generally safe but the PCM is using a default temperature value which may allow slightly higher boost temperatures than ideal. Avoid sustained high-load driving until repaired to prevent potential detonation or pre-ignition.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P00A3 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Forced Induction / Turbocharger System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
