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Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damage of component.

Perform checking procedure as follows.

(1)

Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.

(2)

Check connecting condition of ECM and component connector : Check terminal separation, damage of locking device and connecting condition between terminal and wiring.

note

Disconnect the pin which requires checking at male connector and insert it to the terminal at female connector for checking connecting condition. (After checking, reconnect the pin at correct position.)

Is the problem found?

	▶ Repair the trouble causing part and go to "Verification of Vehicle Repair" procedure.
	▶ Go to "Power Circuit Inspection".

Check voltage between Power supply ('TCU-2/GLOW FUSE 10A') terminal of 'AIR FLOW SENSOR' harness connector and chassis ground.

Specification : 10.5V ~ 14.5V

Is the measured value within specification?

▶ Go to "Signal Circuit Inspection".

▶ If no voltage is detected, repair open / short to ground between Power supply terminal of 'TCU-2/GLOW FUSE 10A' harness connector and Power supply terminal of 'AIR FLOW SENSOR' harness connector, and go to "Verification of Vehicle Repair" procedure.

▶ If the voltage is high than specification value, repair short to battery between Power supply terminal of 'TCU-2/GLOW FUSE 10A' harness connector and Power supply terminal of 'AIR FLOW SENSOR' harness connector, and go to "Verification of Vehicle Repair" procedure.

Check voltage between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and chassis ground.

Specification : 4.8V ~ 5.1V

Is the measured value within specification?

▶ Go to "Ground Circuit Inspection".

▶ If no voltage is detected, go to go to check open / short to ground in signal circuit" as follows.

▶ If the voltage is high than specification value, repair short to battery between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and 'AMS signal' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure.

Check resistance between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and chassis ground.

Specification : Continuity (Below 1.0Ω)

Is the measured value within specification?

	▶ Repair short to ground between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and 'AMS signal' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure.
	▶ Repair open between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and 'AMS signal' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure.

Check voltage between 'AMS signal' terminal of 'AIR FLOW SENSOR' harness connector and chassis ground. (Measurement 1)

Check voltage between 'AMS signal' terminal and 'AMS ground' terminal of 'AIR FLOW SENSOR' harness connector. (Measurement 2)

Specification : [Measurement 1] Voltage - [Measurement 2] Voltage = below 200mV

Is the measured value within specification?

▶ Go to "Component Inspection" procedure.

▶ If "[Measurement 2] voltage" is not detected, repair open between 'AMS ground' terminal of 'AIR FLOW SENSOR' harness connector and 'AMS ground' terminal of ECM harness connector, and go to "Verification of Vehicle Repair".

▶ If the measured value is above 200mV, eliminate the causes of excessive resistance between 'AMS ground' terminal of 'AIR FLOW SENSOR' harness connector and 'AMS ground' terminal of ECM harness connector, and go to "Verification of Vehicle Repair".