P2DBA

Code

Generic P — Powertrain

Battery Charging System B High Voltage Interlock Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 40 EN: 29 RU: 20

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Page language: EN

Causes

Open or short to battery positive in the HV interlock wiring
Damaged or corroded HVIL connector or pin
Faulty HVIL switch, sensor, or harness within the charging module or battery pack
Poor ground or reference at the charging module/ECU input
Water intrusion, contamination or mechanical damage to HV enclosure seals
Failed charging module or ECU input circuit

Symptoms

Battery charging disabled or reduced charging rate
Charge cycle aborts or does not start
Hybrid/EV or charging-system warning lights and messages on dash
Vehicle may enter limp-home or reduced-power mode
Intermittent or persistent DTC present (P2DBA) and possible multiple related HVIL codes

What to check

Retrieve freeze frame and full DTC data; note conditions when the code set
Check for any other HV or charging-related codes stored
Visually inspect HVIL wiring, connectors, and interlock points for damage, corrosion, or intrusion
Verify fuses, service disconnects, and accessory relays related to the charging/interlock circuit
Confirm proper sealing of HV enclosures and that all HV connectors are fully mated
Follow manufacturer procedure to isolate the high-voltage system before any invasive tests

Signal parameters

Expected HVIL closed state: low voltage near chassis reference (typically
Expected HVIL open/fault state: higher voltage toward HV battery or supply reference (varies by system; often battery pack voltage or a defined pull-up)
Controller input expects a defined range; P2DBA indicates voltage above the upper threshold for a valid closed/interlock signal
Measurements must be performed only with the high-voltage system isolated and using HV-rated meter and PPE

Diagnostic algorithm

Read and record all related codes and freeze-frame data. Do not clear codes yet.
Check service documentation for manufacturer-specific HVIL wiring diagrams, pinouts and expected voltage thresholds.
Visually inspect all HV interlock connectors, seals, and harness routing for mechanical damage, corrosion, or water ingress.
With the vehicle powered down and the high-voltage system isolated per manufacturer safety procedure, verify continuity of the HVIL loop from the charging module/ECU to the battery pack interlock points. Expect near-zero continuity when loop closed; refer to spec.
If continuity is not as expected, isolate segments to locate open or short-to-voltage. Repair or replace damaged wiring or connectors.
If wiring checks are good, re-energize the system following safety procedures and measure the HVIL input voltage at the controller with a HV-rated meter to confirm high-level fault. Compare to manufacturer limits.
If input remains high with wiring verified, suspect a failed interlock switch/sensor inside the battery/charger assembly or a faulty controller input. Consult OEM service manual for module removal/inspection or replacement criteria.
After repairs, clear codes, perform available relearn or service procedures, and verify normal charging and that the code does not return during multiple charge cycles.

Likely causes

HVIL wiring damaged at a connector or through-body harness (chafing, crushed)
Connector backshell, pin corrosion or bent pins causing high resistance or intermittent contact
Interlock loop wiring shorted to high-voltage source or to a supply rail
HVIL sensor/switch inside the battery pack or charger has failed
Fuse or service disconnect related to the interlock circuit blown or open

Fault status

⚠️ Status

HV Interlock Circuit B voltage above allowable range. Charging system may be disabled and vehicle charging/drive modes restricted until fault is resolved.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1-3 hours