OBD Guide

P303B

Hybrid/EV Battery Interface Control Module 12 Not Programmed

P303B is an OBD-II diagnostic trouble code meaning: Hybrid/EV Battery Interface Control Module 12 Not Programmed. Common causes: battery management module was not programmed after replacement, module software failure. Estimated repair cost: $56–222.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–222 (est.)

Symptoms

  • Check Engine light comes on
  • Vehicle power limitation
  • Inability to start the engine
  • Error message on display
  • Reduced performance of the hybrid system

Causes

  • Battery management module was not programmed after replacement
  • Module software failure
  • Problems with communication between modules
  • Incorrect module installation
  • Module memory corruption

How to Fix

  1. Diagnostics using a specialized scanner for hybrid/electric vehicles
  2. Reprogramming the Battery Management Module
  3. Checking the module connections and wiring harness
  4. System Software Update
  5. If necessary, replace the control module

Related codes

FAQ

What does the P303B code mean?

P303B is an OBD-II diagnostic trouble code that indicates: Hybrid/EV Battery Interface Control Module 12 Not Programmed

What causes a P303B error code?

The most common causes of P303B include: Battery management module was not programmed after replacement; Module software failure; Problems with communication between modules; Incorrect module installation.

How do I fix a P303B diagnostic trouble code?

To fix P303B: Diagnostics using a specialized scanner for hybrid/electric vehicles. Reprogramming the Battery Management Module. Checking the module connections and wiring harness. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P303B?

Do not drive — repair immediately

How much does it cost to fix P303B?

The estimated repair cost for P303B is $56–222. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat