Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination,deterioration, or damage.
Has a problem been found?
YES
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO
▶ Go to " Power Circuit Inspection " procedure.
Check Power Supply
Ignition "OFF"
Disconnect MAFS connector.
Ignition " ON " & Engine "OFF"
Measure voltage between terminal 4 of MAFS harness connector and chassis ground.
Specification : Approx. B+
Is the measured voltage within specifications?
YES
▶ Go to " Check MAFS Power " as below.
NO
▶ Check that Fuse is installed or blown off between control relay and MAF sensor.
▶ Check open in harenss between control relay and MAF sensor.
Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
Check MAFS Power
Ignition "OFF"
Disconnect MAFS connector.
Ignition "ON" & Engine "OFF"
Measure voltage between terminal 2 of MAF sensor harness connector and chassis ground.
Specification : Approx. 5V
Is the measured voltage within specifications?
YES
▶ Go to " Signal Circuit Inspection " procedure.
NO
▶ Check open in harenss between control relay and MAF sensor.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
Check for short to ground in harness.
Ignition "OFF"
Disconnect MAF sensor connector.
Measure resistance between terminal 1 of MAFS harness connector and chassis ground.
Specification : Infinite
Is the measured resistance within specifications?
YES
▶ Go to " Check for open in harness " as below.
NO
▶ Check short to ground in signal harness.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
Check for open in harness
Ignition "OFF"
Disconnect MAFS and PCM connector.
Measure resistance between terminal 1 of MAFS harness connector and terminal 15 / C21-C of PCM harness connector.
Specification : Approx. below 1Ω
Is the measured resistance within specifications?
YES
▶ Go to " Component Inspection " procedure.
NO
▶ Check open in harenss between MAFS connector and PCM connector.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.