Using Engine Signal Monitor

Using Special Service Tools (Engine Signal Monitor)
1. Check the mass air flow sensor for damage and cracks.
2. Remove the PCM.




3. Connect the Special Service Tools to the PCM.




4. Measure the voltage at the PCM terminal as shown in the table.




5. If not as specified, inspect harness continuity:
- Between PCM terminal 3E and mass air flow sensor terminal B
- Between PCM terminal 4D and mass air flow sensor terminal A
- Between PCM terminal 4A and mass air flow sensor terminal C

6. If there is incorrect terminal voltage or harness continuity, replace the mass air flow sensor.