B0563

Code

Generic B — Body

Body Control Module Internal Fault

Brand: Generic

Type: B — Body

Views: UK: 7 EN: 10 RU: 11

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Internal BCM hardware failure (MCU, internal power regulator, etc.)
Corrupted or failed firmware/EEPROM configuration
Intermittent or incorrect supply voltage (battery/fuse/ignition circuit)
Poor ground or high resistance in ground circuit
CAN/LIN bus communication faults or loss of network messages
Water intrusion, connector corrosion or physical damage to BCM

Symptoms

Multiple body functions intermittent or inoperative (lighting, locks, windows, wipers)
Malfunction indicator lamps or erratic dashboard behavior
Loss of remote keyless entry or central locking
Interior lights, courtesy lights, or warning chimes not functioning correctly
Stored network communication faults (CAN/LIN) or repeated BCM reset events

What to check

Scan BCM with an OEM-level scan tool: read freeze frame, fault history, event counters and stored internal fault data
Verify battery voltage at rest and with ignition on (nominal 12.0–14.5 V)
Inspect BCM connectors for corrosion, bent pins, water ingress, or damaged seals
Check related fuses and fusible links for continuity and correct rating
Measure ground resistance from BCM chassis ground to battery negative (should be low)
Monitor CAN/LIN bus activity with scope or bus analyzer: check for message traffic, error frames and bus voltage levels

Signal parameters

Battery/supply voltage to BCM (V)
Ignition/switched supply presence and drop under load (V)
Chassis/BCM ground resistance (ohms)
CAN bus dominant/recessive voltages (V) and message traffic (packets/sec)
Number of internal watchdog resets or reset counters
EEPROM/firmware checksum and software part numbers

Diagnostic algorithm

Connect OEM-capable scan tool and record all BCM fault codes, freeze frame and event logs. Note history of resets or communication loss.
Verify battery state of charge and charging system operation. Charge battery if low and retest.
Visually inspect BCM enclosure and connectors for moisture, corrosion, or physical damage. Repair or clean as needed.
Verify power and ground circuits: check fuses, measure supply voltage at module pins with ignition OFF/ON, and check ground resistance.
Monitor CAN/LIN bus while operating affected functions. Confirm BCM receives and transmits expected frames and there are no error frames or bus idling.
If communication is intermittent, wiggle test harness and connectors while monitoring live data to reproduce fault.
If supply/ground and network are good but internal faults persist, check for available software/firmware updates or reprogramming procedures per manufacturer service information.
If reflash/reprogramming cannot clear internal fault or module reports hardware failures, consider replacement of BCM. Follow correct replacement, security pairing and coding procedures.
After repair or replacement, clear codes and perform full functional test of body systems and network stability. Re-scan for reappearance of B0563.

Likely causes

Corrupted EEPROM or firmware preventing normal operation
Failed internal regulator or power stage inside the BCM
Intermittent supply or ground causing internal resets
Network communication loss causing internal watchdog/timeouts

Fault status

⚠️ Status

Internal fault detected in Body Control Module (BCM). Module reports an internal error or is not operating correctly; communication and internal diagnostics recommend further testing.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours