Manifold Absolute Pressure Sensor And Intake Air Temperature Sensor, Checking: Notes

The following procedure is used to diagnose the Manifold Absolute Pressure (MAP) Sensor -G71- and Intake Air Temperature (IAT) Sensor -G42- which is controlled byEngine Control Module -J623-.

Special tools and workshop equipment required 

• multimeter.
• Wiring diagram.

Test requirements 

• The Engine Control Module (ECM) -J623- fuse OK.
• Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• Vehicles with automatic transmission, shift selector lever into position "P" or "N".
• A/C switched off.
• Ground (GND) connections between engine/transmission/chassis OK.
• Coolant Temperature at least 80° C.
• Ignition switched off.

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK .

Start diagnosis 

-- Connect the scan tool.

-- Start engine and let it run at idle.

-- Using the scan tool, Check the temperature of the Manifold Absolute Pressure (MAP) Sensor -G71- and Intake Air Temperature (IAT) Sensor -G42- at idle:

Diagnostic text		Specified value
Intake air temperature sensor
Engine running at idle		approx. ambient temperature

-- End diagnosis and switch ignition off.

If the specified value was obtained, but the DTC memory has a DTC indicating a Manifold Absolute Pressure (MAP) Sensor -G71- /Intake Air Temperature (IAT) Sensor -G42- fault:

-- Check the voltage supply of the Manifold Absolute Pressure (MAP) Sensor -G71- /Intake Air Temperature (IAT) Sensor -G42- CHECKING VOLTAGE SUPPLY .

If specified value was not obtained:

-- Check the wiring of the Manifold Absolute Pressure (MAP) Sensor -G71- /Intake Air Temperature (IAT) Sensor -G42- CHECKING ELECTRICAL CIRCUIT .