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Home >> Volvo >> 2002 >> V70 Base, 2.4 61, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes (DTC) - 5 Of 14 >> ECM-2A2A: Rear Heated Oxygen Sensor (Ho2S) Preheating. Signal Too Low. Permanent Fault (B5234T3; B5244T3; 2001) >> Signal too low. Permanent fault >> Checking wiring and components >> Notes
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Checking wiring and components: Notes

Check heated oxygen sensor (HO2S) resistance between #1 and #2.

Check signal cable between heated oxygen sensor (HO2S) #2 and engine control module (ECM) #A35 (#A35) for a short-circuit to ground according to Short-circuit to ground, permanent faults .

Remedy as necessary.

Other information 

Fig 1: Identifying Rear Heated Oxygen Sensor Connector
GLL104128Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 2: Identifying Ohmmeter
GLL101042Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 3: Identifying Rear Heated Oxygen Sensor
GLL102934Courtesy of VOLVO CARS OF NORTH AMERICA.