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Home >> Volvo >> 2004 >> V40 Base >> Repair and Diagnosis >> Engine Performance >> System >> Dynamic Stability Assist (DSA) & Engine Control Module (ECM) Diagnostic Trouble Codes >> ECM-0A: Atmospheric Pressure Sensor Signal. Signal Too Low. Intermittent Fault (B4204T2 CVVT; 2000) >> Signal too low. Intermittent fault >> Checking wiring
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Checking wiring

Check the engine control module (ECM) and atmospheric pressure sensor connectors for contact resistance and oxidation according to Contact resistance and oxidation .

Check in particular for damage, or loose terminal pins.

Check the signal cable between engine control module (ECM) terminal 18 and atmospheric pressure sensor terminal 3 for an intermittent short-circuit to ground. Remedy according to Short-circuit to ground, intermittent faults and for an intermittent open-circuit according to Open-circuit, intermittent faults .

Check the voltage cable between engine control module (ECM) connector terminal 78 and atmospheric pressure sensor terminal 1 for an intermittent open-circuit. Remedy according to Open-circuit, intermittent faults .

The supply voltage should be 5 V.

Other information: 

Fig 1: Identifying Atmospheric Pressure Sensor Connector Terminals
GLL111982Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 2: Identifying Ohmmeter
GLL101042Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 3: Identifying EMS2000
GLL111998Courtesy of VOLVO CARS OF NORTH AMERICA.