P2CB0: Charge Air Cooler Coolant Pump B Performance

What it means

Charge air cooler coolant pump B reports a performance condition. CAC coolant loop circulation is impaired.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

Coolant pump B circulates coolant through the charge air cooler loop so the cooler can reduce compressed intake-air temperature. This performance code sets when the pump is operating but its output or the loop's circulation is inadequate, including when pump output has degraded or air is trapped in the loop.

Common causes

Most likely first.

1. Pump output degraded with age
2. Air pocket in coolant loop

Symptoms

• Check-engine light
• Reduced engine power or acceleration
• Possible charge-air temperature warning

How to diagnose it

1. Save freeze-frame data and compare charge-air temperature behavior with engine load to see when pump B's cooling performance falls short.
2. Check the charge air cooler loop coolant level using the vehicle's specified checking procedure, and look for visible leaks.
3. Inspect pump B, its connector, and accessible hoses for damage, looseness, kinks, or signs of poor circulation.
4. Use a scan tool output test if supported and verify that pump B runs while observing coolant movement using the vehicle's service procedure.
5. If level, wiring, and visible flow are satisfactory, test pump B output and the loop for restriction or trapped air according to the manufacturer's procedure.

Common fixes

• Top up the charge air cooler loop with the specified coolant if low, and repair any leak found.
• Bleed trapped air from the loop using the manufacturer's procedure.
• Repair a kinked, restricted, or leaking hose in the pump B circuit.
• Replace pump B if its flow remains inadequate after the loop and connections are verified.

Can I keep driving?

Avoid hard acceleration, towing, and long climbs because inadequate charge-air cooling can trigger reduced power and increase thermal stress. Stop if a charge-air temperature warning appears or engine performance deteriorates sharply.