P0439 Volvo 760 OBD Code

OBD/2 P0439 error code description and symptoms.

HO2S Sensor Circuit Malfunction (HO2S-11) During testing the HO2S Heaters are checked for opens/shorts and excessive current draw.
The test fails when current draw exceeds a calibrated limit and/or an open or short is detected. Short to VPWR in harness or HO2S. Water in harness connector. Open VPWR circuit. Open GND circuit. Low battery voltage. Corrosion or poor mating terminals and wiring Damaged HO2S heater. Damaged PCM.

At this point we are assuming that the fuses and relays are good. You will need to locate the PCM/TCM and the power input signal circuit using your vehicle information source. Unplug the connector from the PCM/TCM, place the ignition switch in the ON position, and probe the appropriate circuit with the positive test lead of the DVOM.

P0439 Volvo 760 Error Code Repair Process :

OBD P0439 code and tailpipe testing are two different approaches to identify vehicles in need of repair. The OBD system looks for broken or malfunctioning emissions control components and p0439 catalyst heater control circuit bank 2, while tailpipe tests sample a vehicle's exhaust to see if it is above or below certain prescribed limits. Given the robust nature of today's emissions control components, it is entirely possible for an individual component to P0439 malfunction without leading to an immediate increase in emissions at the tailpipe. In such cases, other components (like the catalyst) can temporarily compensate for the part that is broken however, these other components can only do double duty for so long before they, too, begin to malfunction. In addition, OBD also monitors for P0439 and other malfunctions in the fuel system problems that traditional tailpipe tests were not designed to identify. Most state and local areas also include a gas cap pressure test as part of an emission inspection.

Common Causes of Volvo 760 P0439 OBD2 Code

A common cause of code P0439 is the failure of P0439 Catalyst Heater Control Circuit Bank 2, but there are several other possible causes as well, such as ;

Exhaust tube
Faulty Air Flow Meter
Faulty spark plug (s)
Missing or loose fuel cap

P0439 is a kind of Powertrain Trouble Code

Powertrain of a modern automobile, comprising engine (with exhaust system), transmission, drive shaft, suspension and the wheels. In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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P0439 Volvo 760 OBD Code

P0439 Volvo 760 Error Code Repair Process :

Common Causes of Volvo 760 P0439 OBD2 Code

P0439 code for other Volvo cars