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Home >> Volvo >> 2004 >> S80 Base, 2.5 59, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes - 5 Of 11 >> ECM-2A2A: Rear Heated Oxygen Sensor (Ho2S) Preheating. Signal Too High. Permanent Fault (B6284T; 1999-2001) >> Signal too high. 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 control module #A35 (#A35) for a short-circuit to supply voltage according to Short-circuit to supply voltage. Permanent faults .

HINT: Use a test lamp with at least a 3 W bulb to determine whether the cable is short-circuited to supply voltage. 

Remedy as necessary.

Other information 

Fig 1: Identifying Heated Oxygen Sensor
GLL104128Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 2: Identifying Voltage Display
GLL101041Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 3: Identifying Rear Heated Oxygen Sensor
GLL102934Courtesy of VOLVO CARS OF NORTH AMERICA.