Code Definition

P0429 — Catalyst heater Circuit control malfunction bank 1

System: Powertrain  |  Type: Generic (OBD-II Standard)  |  Make: Generic

About P0429

P0429 is a generic (obd-ii standard) powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P0429 is stored, the module has detected a bank-specific fault, meaning it applies only to one cylinder bank of a multi-bank engine.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

Because P0429 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.

Code Information

The powertrain control module (PCM) sets P0429 when it detects a malfunction in the catalyst heater control circuit on Bank 1. Some vehicles use a heated catalyst system to quickly bring the catalytic converter up to operating temperature, improving emissions performance. This fault indicates an issue with the control circuit, which may be due to an electrical problem or a failing heating element.

Quick Facts