B2773

Code

Generic B — Body

Body Control Module Internal Memory Fault

Brand: Generic

Type: B — Body

Views: UK: 13 EN: 19 RU: 13

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Low or unstable battery voltage or voltage spikes during write operations
Poor power or ground connections to the BCM
Water intrusion, corrosion, or physical damage to the BCM or connector
Failed or degraded internal EEPROM/flash memory
Interrupted or failed software update/reflash
Module hardware failure or age-related degradation

Symptoms

Illuminated malfunction indicator lamp or BCM-related warning
Loss or intermittent operation of body functions (lights, locks, windows, wipers)
Vehicle security/immobilizer faults or no-start conditions
Module not responding to diagnostic scan tool or intermittent communication
Stored BCM-related DTCs and possible multiple related codes on CAN network
Unexpected resets, erratic behavior, or retained incorrect configuration settings

What to check

Read all stored DTCs (including historical) and freeze frame with a capable scan tool
Check battery state-of-charge and charging system voltage (key ON, engine running)
Inspect BCM power and ground circuits, battery terminals, and chassis grounds
Inspect BCM connectors for corrosion, bent pins, water intrusion, or physical damage
Verify fuses/relays for BCM power feeds are good and correct rated
Check CAN/LIN bus activity and module communications for errors

Signal parameters

Battery voltage at BCM (Key ON and cranking)
Accessory/ignition feed voltages to BCM
Ground voltage drop across BCM ground points
CAN bus RX/TX message activity and error counters
Module watchdog reset count and last reset cause (if available)
EEPROM/flash checksum or memory status flags reported by BCM

Diagnostic algorithm

Capture and document all DTCs, freeze frame data, module part number, and software/calibration levels.
Verify battery health and charging system (minimum ~12.4 V at rest; >13.5 V running). Recharge or replace weak battery before further tests.
Inspect BCM physical condition and harness: disconnect battery, remove BCM cover if required, look for water, corrosion, damaged pins, or burned traces.
With battery reconnected, backprobe/check BCM power and ground pins for correct voltages and low resistance to battery/ground while exercising accessories.
Check fuses/relays and verify they supply correct voltage to the BCM; repair any wiring faults.
Use a scan tool to monitor CAN bus and verify the BCM is communicating. If multiple modules fail, isolate bus wiring and power distribution.
If power/ground and communications are good but memory fault persists, check for recent programming attempts. Re-attempt reading module memory dump or error log if supported.
If supported by OEM/data, attempt a non-destructive reflash or restore of BCM software and calibration using manufacturer procedures. Ensure stable power during reflash (use battery charger).
If reflash fails or memory reports hardware faults (EEPROM/flash failure), the BCM may need replacement and reprogramming/configuration. Follow anti-theft pairing and VIN programming procedures.
After repair/reprogram, clear codes and verify normal operation and no recurrence over an appropriate drive cycle.
Safety note: Follow manufacturer service procedures for module programming, immobilizer pairing, and battery handling. Avoid partial or interrupted reprogramming.

Likely causes

Corrupted EEPROM/flash due to interrupted reprogramming or voltage loss during write
Weak battery/voltage transients causing write failures or checksum errors
Poor ground or power integrity at the BCM
Internal memory hardware failure within the BCM

Fault status

⚠️ Status

Stored DTC B2773: Body Control Module internal memory/EEPROM/flash fault detected. Module reports corrupted or unreadable internal memory, checksum failure, or related internal storage error.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1.0-3.0 hours