Catalyst Heater
A resistive element that warms an electrically heated converter before or during a cold start, cutting the light-off delay further than a close-coupled position alone can. Uncommon on ordinary production vehicles and more usual on hybrids and low-emission variants. Because the heater is part of the assembly, an efficiency fault may be a heater fault rather than a catalyst fault — a converter that never reaches temperature in time fails its monitor with an undamaged substrate.
Also known as: heated catalyst, catalyst heating element, electrically heated catalyst, ehc
Referenced by 20 codes
Codes involving this component (20)
- P0423 Heated Catalyst Efficiency Below Threshold — Bank 1 Moderate
- P0424 Heated Catalyst Temperature Below Threshold — Bank 1 Moderate
- P0433 Heated Catalyst Efficiency Below Threshold — Bank 2 Moderate
- P0434 Heated Catalyst Temperature Below Threshold — Bank 2 Moderate
- P2AB1 Catalyst Heater Control Module Performance Moderate
- P2AB2 Catalyst Heater Control Module Supply Voltage Moderate
- P0429 Catalyst Heater Control Circuit/Open Bank 1 Low
- P0439 Catalyst Heater Control Circuit/Open Bank 2 Low
- P04F2 Catalyst Heater Supply Voltage Bank 1
- P04F3 Catalyst Heater Supply Voltage Bank 2
- P04F4 Catalyst Heater Circuit Low Bank 1
- P04F5 Catalyst Heater Circuit Low Bank 2
- P04F6 Catalyst Heater Circuit High Bank 1
- P04F7 Catalyst Heater Circuit High Bank 2
- P04F8 Catalyst Heater Circuit Intermittent Bank 1
- P04F9 Catalyst Heater Circuit Intermittent Bank 2
- P04FE Catalyst Heater Circuit Performance Bank 1
- P04FF Catalyst Heater Circuit Performance Bank 2
- U01B5 Lost Communication With Catalyst Heater Control Module
- U04B6 Invalid Data Received From Catalyst Heater Control Module
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Exhaust Pressure Control Valve 56
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Secondary Air Injection Pump 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Particulate Matter Sensor 24
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Temperature Sensor 20
- Fuel Filler Cap 18
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
Information, not instruction
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