Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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With SST-New Generation Star Tester

MASS AIR FLOW SENSOR
Inspection
Using SST-New Generation Star Tester (NGS)
1. Check the mass air flow sensor for damage and cracks.
2. Warm up the engine to normal operating temperature.
3. Shift the selector lever to R
4. Turn off all electric loads.
- Headlight
- Blower motor
- Rear window defroster
- Power steering
5. Wait until the cooling fan stops.




6. Connect the SSTs (NGS) to the data link connector 2.
7. Select the PID/DATA MONITOR AND RECORD function of the NGS.




8. Select "MAF V" on the NGS display. NGS measures and shows the voltage.




9. If not as specified, perform following inspection.




Harness continuity.
- Between ECM terminal 3E and mass air flow sensor terminal B
- Between ECM terminal 4D and mass air flow sensor terminal A
- Between ECM terminal 4A and mass air flow sensor terminal C
10. If there is incorrect terminal voltage or harness continuity, replace the mass air flow sensor.

Note: The scan tool also shows the mass air flow rate and load value.