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Home >> Volvo >> 2009 >> XC90 R-Design, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes - 2 Of 13 >> ECM-2470: Front Heated Oxygen Sensor (Ho2S), Bank 1. Faulty Signal (B5254T2; 2005-2007) >> Signal Too High / Signal Missing / Faulty Signal >> Checking The Components And Wiring
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Checking The Components And Wiring

CAUTION:

Do not apply rust solvent spray or grease to the heated oxygen sensor (HO2S) connector.

Check the heated oxygen sensor (HO2S) connector. Check for contact resistance and oxidation.

Check the cable between engine control module (ECM) terminal #A28 (#A28) and heated oxygen sensor (HO2S) terminal #2. Check for an open-circuit.

NOTE:

If possible, measure from the rear of the affected connectors in order to minimize any damage and future loose connections.

Try a new heated oxygen sensor (HO2S) if the above fault-tracing does not remedy the fault.

Remedy as necessary.

Other information 

Fig 1: Identifying Front Heated Oxygen Sensor Connector Terminals
GLL104133Courtesy of VOLVO CARS CORPORATION
Fig 2: Identifying VCT2000 Diagnostic Tool Symbol In VIDA
GLL100563Courtesy of VOLVO CARS CORPORATION
Fig 3: Front Heated Oxygen Sensor
GLL102931Courtesy of VOLVO CARS CORPORATION