U0313

Code

Generic U — Network/User

Software Incompatibility With Battery Energy Control Module B

Brand: Generic

Type: U — Network/User

Views: UK: 31 EN: 39 RU: 32

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Incompatible or mismatched software/firmware version on BECM B
Incomplete or corrupted reflash/programming
Replacement module programmed with wrong calibration or VIN
CAN bus communication errors or message corruption
Low battery voltage or interruption during module programming
Connector corrosion, damaged wiring, or poor ground to BECM B

Symptoms

Battery management warnings or traction/battery warning lamp on dash
Reduced charging or regenerative braking functionality
Vehicle enters limited-performance (limp) mode
Stored multiple U-codes and related battery control faults
Loss or intermittent loss of messages from BECM B on diagnostic scan tool
Failure to accept programming or programming error messages

What to check

Retrieve freeze-frame and all stored DTCs from all modules with a capable OEM or dealer-level scan tool
Confirm vehicle VIN and calibration IDs reported by BECM B and other related modules
Check history for recent software updates, module replacements, or service events
Verify battery pack voltage and state of charge; ensure proper support voltage during programming
Inspect BECM B connectors and wiring for damage, corrosion, or water intrusion
Scan CAN bus to confirm BECM B node presence and message activity

Signal parameters

BECM_B: SWVersion / HWVersion / CalibrationID (string identifiers)
CAN Node Address and CAN IDs for BECM B messages
Message Periodicity (expected update interval, e.g., 10–1000 ms)
Checksum/CRC fields or diagnostic session response validity
BatteryPackVoltage (pack V range per vehicle), expected nominal at key-on
StateOfCharge (0–100 %) and CellTemperatures (°C) reported by BECM B

Diagnostic algorithm

Connect an OEM-capable scan tool and record U0313 plus any related codes from all modules
Confirm battery pack voltage is within manufacturer-specified range and connect a battery conditioner if required for programming
Verify BECM B reports SW/HW/Calibration IDs; record values for comparison with factory data
Check service history: was BECM B recently replaced or reflashed? Note tool and software versions used
Inspect physical connectors, wiring, and grounds for damage or contamination; repair as needed
Monitor CAN bus traffic with a capable tool or oscilloscope to verify BECM B message ID presence, timing and signal integrity
If communication is present but software mismatch exists, obtain correct OEM software/calibration and attempt to reprogram BECM B following manufacturer procedures (ensure stable power during reflash)
After reprogramming, clear all codes, perform relearn procedures per manufacturer, and road-test to confirm fault does not return
If module will not accept correct programming or continues to report incompatibility, replace BECM B with correct part and program to vehicle VIN and calibration levels
If problems persist after replacement and programming, escalate to OEM technical support and check for TSBs or known module family incompatibilities

Likely causes

Incomplete or failed software update of BECM B
Replacement BECM B not programmed to vehicle VIN or wrong calibration
CAN bus message checksum/format mismatch after software change
Battery voltage drop during programming corrupted module software

Fault status

⚠️ Status

Software incompatibility detected between Battery Energy Control Module B and vehicle control network. Module may reject or mismatch messages, causing limited battery control functions. Reprogramming or replacement and correct calibration are typically required.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1.5-4.0 hours