P2DB6

Code

Generic P — Powertrain

Battery Charger B Cooling System Performance

Brand: Generic

Type: P — Powertrain

Views: UK: 41 EN: 43 RU: 27

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Low coolant level or air trapped in cooling circuit
Clogged heat exchanger or coolant passages in charger or radiator
Cooling pump failure or reduced pump output
Cooling fan inoperative or insufficient airflow
Stuck or malfunctioning thermostat or bypass valve
Faulty coolant temperature sensor or flow sensor for Charger B

Symptoms

Charge rate for battery B reduced or charger derated
Warning message or MIL related to charging/cooling
Charger B temperature readout higher than normal in live data
Cooling fan running constantly or not running when commanded
Visible coolant leak or low reservoir level
Reduced vehicle performance or charger unavailable until cooled

What to check

Scan for stored and pending codes; record freeze-frame and freeze data
Inspect coolant reservoir level and coolant condition
Visually inspect hoses, heat exchanger, radiator, connectors and clamps for leaks or blockages
Verify fuses and relays related to charger cooling, pump and fan
Use scan tool to view live parameters: charger coolant temp, pump command, pump current, flow sensor, fan command and RPM
Directly verify fan and pump operation (bench or powered) if safe to do so

Signal parameters

Battery Charger B coolant temperature (°C) — expected: within pack/ambient dependent normal range; monitor for abnormal rise
Target coolant temperature or setpoint (°C)
Coolant pump command (ON/OFF or PWM duty %) and pump current (A) — verify pump draws within spec
Coolant flow sensor voltage/frequency or flow rate (L/min) if equipped
Cooling fan command (ON/OFF or PWM %) and fan RPM
Supply voltage to pump and fan (V) — should be battery voltage when commanded

Diagnostic algorithm

Retrieve P2DB6 and any related codes; note freeze-frame data and recent drive conditions.
Visually inspect coolant reservoir, hoses, heat exchanger and connections for leaks, low level or contamination; top up and pressure-test cooling system if low.
With scan tool, monitor Charger B coolant temp, pump command and pump current while attempting a charging event or a commanded pump run.
Verify pump operation: command pump ON via scan tool or apply fused battery voltage directly to pump (manufacturer procedure) and confirm flow/pump current is within spec.
Check cooling fan operation and airflow; command fan ON via scan tool or test directly. Inspect radiator/heat exchanger for debris blocking airflow.
Test temperature and flow sensors: compare sensor reading to known-good reference or inspect signal voltage/frequency and resistance per service data.
Inspect fuses, relays and wiring for continuity, corrosion or damaged insulation. Repair connectors and repair grounds as required.
If flow is restricted, remove and inspect heat exchanger/charger coolant passages; clean or replace clogged components.
After repair, clear codes and perform a charge cycle/road test while monitoring live data to confirm temps, flow and absence of code recurrence.
If all hardware checks good and problem persists, consider module software update or replacement following manufacturer guidance.

Likely causes

Low coolant level or air in circuit
Cooling pump electrical fault or mechanical failure
Blocked heat exchanger/coolant passages
Cooling fan not providing required airflow
Faulty temperature/flow sensor or connector

Fault status

⚠️ Status

Stored when the control module detects cooling performance for Battery Charger B outside expected thresholds. May set MIL/warning, store freeze-frame data and cause charger derate or disable until temperatures return to safe range.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours