OBD-II DTC · SAE J2012

B3A04

A/C Refrigerant Distribution Valve C Control Circuit Driver Current/Temperature Too High

Cooling System → Depends on cause

What B3A04 means

B3A04 is a standard SAE J2012 powertrain diagnostic trouble code with the defined meaning: A/C Refrigerant Distribution Valve C Control Circuit Driver Current/Temperature Too High. This is the OEM-agnostic definition; specific manufacturer interpretation may add detail (subsystem, bank, sensor location) but the core meaning is consistent across all OBD-II compliant vehicles since 1996.

Common symptoms when B3A04 is active

Coolant temp sensor MIL, fan stays on / off, thermostat performance DTC, heater core slow to warm.

Can this code be suppressed via ECU tuning?

Whether this code is safe to suppress depends on the underlying cause. Diagnose first, suppress only after confirming the mechanical issue is benign or rectified.

How to remove B3A04 with Softechpro V5

Recommended service: DTC OFF (cooling branch). Step-by-step workflow:

  1. Check the thermostat / sensor / fan circuit physically first.
  2. If the issue is a long-standing nuisance code on an old vehicle, Softechpro V5 DTC OFF can suppress it.
  3. Load .bin, select cooling DTC group, save, flash.

Softechpro V5 supports 1,400+ ECU firmwares across Bosch (EDC15, EDC16, EDC17, MD1, MG1, ME7, MED17), Siemens / Continental (SID, SIMOS, EMS), Delphi (DCM, DDC), and Magneti Marelli platforms.

Related codes in the B3Axx family

B3A00B3A01B3A02B3A03B3A05B3A06B3A07B3A08B3A09B3A0AB3A0BB3A0C