P00A2
Charge Air Cooler Temperature Sensor Circuit Low Bank 2P00A2 is a generic OBD-II powertrain diagnostic trouble code: Charge Air Cooler Temperature Sensor Circuit Low Bank 2. It is logged by the engine control unit when the powertrain monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.
What P00A2 means
P00A2 is a generic OBD-II powertrain code set when the PCM detects an abnormally low voltage signal from the charge air cooler temperature sensor circuit on engine bank 2. In a standard NTC thermistor circuit, the PCM supplies a 5 V reference through an internal pull-up resistor; as the thermistor's resistance decreases with rising temperature, the signal voltage falls. A circuit low condition means the voltage at the PCM input pin has dropped below the minimum plausible threshold — typically below about 0.1–0.2 V — which indicates the signal wire is shorted to ground either within the harness, at the connector, or inside the sensor itself. This effectively tells the PCM the temperature is impossibly high, causing it to reject the signal and store P00A2. Without a valid temperature reading, the PCM substitutes a default value for boost management and fuelling corrections, which degrades engine performance and emissions control. On diesel vehicles, DPF regeneration strategies are often suspended when a charge air temperature input is flagged invalid. The fault is commonly caused by damaged wiring insulation allowing the signal wire to contact chassis ground, water ingress into the connector, or a sensor that has developed an internal short.
Common causes
Most-frequently reported root causes when P00A2 is logged.
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1
Internal short circuit within the temperature sensor (signal pin shorted to ground inside the sensor body)
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2
Chafed or pinched wiring harness allowing the signal wire to contact bare metal or chassis ground
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3
Water or oil ingress into the sensor connector creating a low-resistance leakage path to ground
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4
Corroded connector terminals with moisture bridging the signal and ground pins
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5
Incorrectly routed replacement harness contacting hot or sharp engine components that damaged the insulation
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6
Failed charge air cooler with internal damage that has physically crushed the sensor wiring
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7
Faulty PCM input channel with an internal short on that circuit (rare)
Symptoms drivers notice
How to diagnose P00A2
A typical diagnostic flow when this code is present.
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1
Connect a scan tool and observe the bank 2 charge air cooler temperature live data; a circuit-low fault typically displays an extreme high temperature value or a sensor error flag rather than a realistic reading
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2
With the ignition on and engine off, back-probe the sensor signal wire at the connector and measure voltage to ground — less than 0.2 V with the sensor connected confirms the circuit low; it should read around 4.5–5 V with the sensor disconnected
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3
Disconnect the sensor connector; if the voltage at the harness signal pin rises to near 5 V, the short is inside the sensor and it should be replaced
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4
If voltage remains low with the sensor disconnected, the short is in the wiring harness — trace the signal wire from the sensor back toward the PCM, inspecting for abrasion, pinch points, and areas of heat exposure
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5
Check the connector for moisture, corrosion, or debris bridging the signal and ground terminals; clean with electrical contact cleaner and inspect terminal condition
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6
After repairing the short circuit or replacing the sensor, verify the reference voltage is stable at 4.5–5 V and the signal voltage changes smoothly as the engine warms
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7
Clear codes and perform a drive cycle to confirm no recurrence before returning the vehicle to service
Related powertrain codes
Frequently asked questions
Why does a circuit-low fault show an impossibly high temperature on the scan tool?
The NTC thermistor circuit is designed so that lower resistance (higher temperature) produces lower signal voltage. When the signal wire is shorted to ground — zero resistance — the PCM interprets this as an off-the-chart temperature, pegging the reading at maximum and flagging it as implausible.
Can P00A2 appear alongside P00A0 or P00A1?
Yes. P00A0 is a general circuit fault, P00A1 is a range/performance fault, and P00A2 is the specific circuit-low variant. They can appear together if the wiring fault intermittently produces different error conditions, or if the root cause affects both the signal level and its plausibility compared to other sensors.
Is the sensor easy to replace on most vehicles?
Charge air cooler sensors are usually clip-in or single-bolt sensors located on the intercooler housing or the intake duct. They are typically straightforward to access and replace within 30–60 minutes, though the intake duct may need to be partially removed on some vehicles for clear access.
Could engine oil in the intercooler cause P00A2?
Indirectly, yes. Heavy oil accumulation inside the intercooler can coat the sensor tip and — if it penetrates the connector — create a conductive path between terminals. Cleaning the intercooler and connector, then resealing them against further oil ingress, is advisable alongside sensor replacement in such cases.
Disabling P00A2 in software
RaceTune can permanently disable P00A2 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.
ECU families we can disable P00A2 on
We hold the DaVinci A2L disable definitions for these families, so the exact P00A2 path and mask addresses are mapped. verified marks a confirmed disable definition. We support many more — upload your file and our identifier will match it automatically.
- Bosch EDC17C74 verified
Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.
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