LEMON Manuals: Even more car manuals for everyone
Home >> Volvo >> 2013 >> XC90 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Module (ECM) Diagnostic Trouble Codes - 1 Of 13 >> ECM-121D: Mass Air Flow (MAF) Sensor. Signal Too Low (B5254T2; 2005-2007) >> Signal Too Low >> Checking Components And Wiring

Checking Components And Wiring

Check the mass air flow (MAF) sensor connector. Check for contact resistance and oxidation.

Check for air leakage in the intake system and for damage to hoses etc.

Check the power supply cable between system relay terminal #5 and mass air flow (MAF) sensor terminal #2. Check for an open-circuit.

Check the signal cable between engine control module (ECM) terminal #A22 (#A22) and mass air flow (MAF) sensor terminal #5. Check for an open-circuit. Check for a short-circuit to ground.

Check the power supply cable between engine control module (ECM) terminal #A39 (#A39) and mass air flow (MAF) sensor terminal #4. Check for an open-circuit.

HINT: With the ignition on and the mass air flow (MAF) sensor connector connected the voltage at mass air flow (MAF) sensor terminal #2 must be approximately U  bat. 

Remedy as necessary.

Other information 

Fig 1: Identifying Connector
GLL104131Courtesy of VOLVO CARS CORPORATION
Fig 2: Identifying Mass Air Flow (MAF) Sensor
GLL102920Courtesy of VOLVO CARS CORPORATION