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Home >> Volvo >> 2004 >> V40 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes - 3 Of 3 >> ECM-91: Torque Reduction. Signal Missing. Intermittent Fault (B4204T2 CVVT; 2000) >> Signal missing. Intermittent fault >> Checking wiring
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Checking wiring

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

Check in particular for damaged or loose terminal pins.

Check the signal cable between the engine control module (ECM) terminal #20 and DSA control module terminal 15 for an intermittent open-circuit and remedy according to Open-circuit, intermittent faults .

Fig 1: Identifying DSA Control Module Terminals
GLL118762Courtesy 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.