Open or damaged wire in the pump sense circuit, such as a broken conductor or corroded terminal; Short to voltage on the sense circuit, often from chafed insulation against a power wire; Failed charge air cooler coolant pump with an internal open circuit in its feedback element; Poor electrical connection at the pump connector or at the powertrain control module connector; Faulty powertrain control module, though this is rare and should be diagnosed last; Coolant contamination or debris causing the pump to seize and the sense circuit to read out of range

DTC codes / P2Cxx · Hybrid propulsion / P2CA1

P2CA1Charge Air Cooler Coolant Pump Sense Circuit High

Q: What does code P2CA1 mean?

Charge Air Cooler Coolant Pump Sense Circuit High. P2CA1 indicates that the powertrain control module has detected an abnormally high voltage on the sense circuit for the charge air cooler coolant pump, which is the electric pump that circulates coolant through the air-to-liquid intercooler. The computer expects a voltage within a specific range that reflects a valid signal, and a high reading usually means the circuit is open, shorted to voltage, or the pump's internal feedback is missing.

P2CA1 indicates that the powertrain control module has detected an abnormally high voltage on the sense circuit for the charge air cooler coolant pump, which is the electric pump that circulates coolant through the air-to-liquid intercooler. The computer expects a voltage within a specific range that reflects a valid signal, and a high reading usually means the circuit is open, shorted to voltage, or the pump's internal feedback is missing.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaHybrid propulsion

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Reduced engine power or limp mode during heavy acceleration or sustained load
Higher-than-normal intake air temperatures, which may cause power derating
In rare cases, the coolant pump may run continuously or not at all, leading to overheating of the charge air cooler circuit
A stored freeze-frame showing the fault set during high-load or high-temperature conditions

Common causes, most likely first

Open or damaged wire in the pump sense circuit, such as a broken conductor or corroded terminal
Short to voltage on the sense circuit, often from chafed insulation against a power wire
Failed charge air cooler coolant pump with an internal open circuit in its feedback element
Poor electrical connection at the pump connector or at the powertrain control module connector
Faulty powertrain control module, though this is rare and should be diagnosed last
Coolant contamination or debris causing the pump to seize and the sense circuit to read out of range

How to diagnose and fix it

Scan all modules for stored codes and record freeze-frame data to confirm the fault conditions
Visually inspect the charge air cooler coolant pump connector and harness for corrosion, chafing, or loose pins
Measure resistance and voltage on the sense circuit at the pump connector and compare with the manufacturer's specification
Perform a wiggle test on the harness while monitoring the sense circuit voltage to reveal intermittent opens
Check the pump's electrical operation by commanding it on with a scan tool and listening for activation
If the circuit tests good, substitute a known-good pump or perform a resistance check on the pump's feedback circuit
Clear codes and verify the repair by running the engine under load and confirming the sense voltage stays within range

When the sense circuit lies about the pump

A high sense voltage often means the circuit is open rather than the pump being defective, so technicians who replace the pump without checking wiring frequently see the code return.
The charge air cooler coolant pump may share a ground or power feed with other components, and a fault in that shared circuit can set P2CA1 without any problem in the pump itself.
Some vehicles use a pulse-width-modulated signal on the sense circuit, and a standard multimeter may show a misleading average voltage that looks high even when the circuit is functioning normally.
After an engine replacement or front-end repair, the charge air cooler coolant pump harness is easily pinched or left disconnected, which sets this code immediately on the first drive cycle.
A low coolant level or air lock in the charge air cooler circuit can cause the pump to overheat and its feedback signal to go high, so always check coolant condition and level before condemning electrical parts.

Can I keep driving with P2CA1?

You can usually drive the vehicle short distances at light throttle, but avoid heavy acceleration or sustained high-load driving because the charge air cooler may not receive enough coolant flow, leading to reduced power and potential component damage. Have the fault diagnosed promptly to prevent overheating of the intercooler circuit.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.