U0337

Code

Generic U — Network/User

Software Incompatibility With Battery Charger Control Module A

Brand: Generic

Type: U — Network/User

Views: UK: 14 EN: 26 RU: 22

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Battery Charger Control Module A has incorrect or mismatched software/calibration version
Incomplete or failed software update/programming of the charger module
Replacement module not programmed to vehicle or wrong part number
Corrupted module memory or checksum error
Network communication errors (CAN/ LIN) causing corrupted data
Low or unstable battery/voltage during programming or operation

Symptoms

DTC U0337 stored and may be accompanied by other U-codes
Battery charging system warnings or reduced charging functionality
Hybrid/EV charge-inhibit or limp-home behavior (if applicable)
Illuminated master warning or battery-related dash lamp
Intermittent or permanent loss of communication with charger module

What to check

Scan for related DTCs in other modules (look for other U-codes and module-specific codes)
Check freeze frame and stored data for conditions when the code set
Verify vehicle battery voltage and state of charge; ensure stable power
Inspect connectors and wiring to Battery Charger Control Module A for corrosion, damage, or loose pins
Compare part number and software/calibration ID of the charger module to vehicle build data
Check OEM service information/TSBs for required software versions and reflash procedures

Signal parameters

Module source address / Node ID on vehicle network
Network protocol (e.g., CAN, CAN FD, LIN) and bus speed
Message ID(s) used by Battery Charger Control Module A
Data length / DLC and expected message frequency
Software version / calibration ID field transmitted by module
Status or error byte indicating compatibility and checksum/CRC field

Diagnostic algorithm

Retrieve and record all U-codes and freeze frame data from all modules.
Verify battery voltage and ensure charging/starting system is healthy before programming.
Inspect the charger module connector and harness for damage, corrosion, or poor connection; repair as needed.
Use OEM scan tool to read the charger module's part number, software and calibration IDs and compare to vehicle build data and TSB requirements.
Check service history: was the charger module recently replaced or reprogrammed? If yes, confirm correct procedure and software was used.
If software/calibration mismatch is present or unknown, perform the OEM-approved reprogram/flash of Battery Charger Control Module A to the correct software version. Follow battery/voltage precautions.
If reflash fails or module reports memory/checksum errors, consider re-initialization or guided repair procedure from OEM; replace module only if software repair is unsuccessful and hardware tests point to failure.
After reprogramming or repair, clear codes and perform network and functional verification; road test and re-scan for recurrence.
If code returns, capture live data of the charger module messages and perform network diagnostics (check termination resistors, bus integrity, message errors) and consult manufacturer support.

Likely causes

Module was recently replaced or attempted to be reprogrammed without proper flash
Technician used incorrect software calibration or generic reflash file
Battery voltage dropped during a software update and left module in incompatible state
Network wiring fault causing incomplete or corrupted software/version messages
OEM software update required by TSB but not applied

Fault status

⚠️ Status

A software incompatibility was detected between Battery Charger Control Module A and other vehicle control modules or expected software versions. The charger module software/calibration ID or message contents do not match the required values, causing the network or other modules to flag an incompatibility.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours