Intake Manifold Sensor -GX9-, Checking

General Description

Intake manifold pressure and temperature are two factors used for engine load management. They measure the intake air temperature and the intake manifold pressure. The sender is located upstream of the Throttle Valve Control Module -J338- and contains the following senders:

Intake Manifold Temperature Sensor -G72-.
Charge Air Pressure Sensor -G31-.

They Measure The Pressure And Temperature Of The Air In Each Bank. The Values Measured Here Correspond To The Actual Air Mass In Each Bank.

Note the Intake Manifold Temperature Sensor -G72- / Charge Air Pressure Sensor -G31- is also known as the Intake Manifold Sensor -GX9-.

Special Tools And Workshop Equipment Required

Multimeter.
Wiring Diagram.
Scan Tool.

Test Requirements

Fuses OK.
Battery voltage OK.
Switch OFF all electrical and electronic accessories.
Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
Observe all safety precautions: SAFETY PRECAUTIONS .
View clean working conditions: CLEAN WORKING CONDITIONS .

Test Procedure

Step	Procedure	Result / Action to Take
1	PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK . -- Was Complaint verified?	-- YES: GO TO: Step 2 Intake Manifold Sensor -GX9-, CHECKING - 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: ON. DISCONNECT: Intake Manifold Sensor -GX9- harness connector. CHECK: Intake Manifold Sensor -GX9- harness connector terminals 2 to 4 for voltage. SPECIFIED VALUE: About 5.0 V. IGNITION: OFF. -- Was Value obtained?	-- YES: GO TO: Step 3 Intake Manifold Sensor -GX9-, CHECKING - 3 . -- NO: GO TO: Step 4 Intake Manifold Sensor -GX9-, CHECKING - 4 .
3	REMOVE: Engine Control Module - J623-. Refer to the appropriate service information. CHECK: Intake Manifold Sensor -GX9- harness connector terminal 1 to the Engine Control Module - J623- harness connector T94 / 7 for resistance. CHECK: Intake Manifold Sensor -GX9- harness connector terminal 3 to the Engine Control Module - J623- harness connector T94 / 86 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω) -- Were Values obtained?	-- YES: REPLACE: Intake Manifold Sensor -GX9-. Refer to the appropriate service information. GO TO: Step 5 Intake Manifold Sensor -GX9-, CHECKING - 5 . -- NO: PERFORM: Visual Inspection of wiring and component. CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals. REPAIR: Faulty wiring or connector. GO TO: Step 5 Intake Manifold Sensor -GX9-, CHECKING - 5 .
4	REMOVE: Engine Control Module - J623-. Refer to the appropriate service information. CHECK: Intake Manifold Sensor -GX9- harness connector terminal 2 to the Engine Control Module - J623- harness connector T94 / 63 for resistance. CHECK: Intake Manifold Sensor -GX9- harness connector terminal 4 to the Engine Control Module - J623- harness connector T94 / 38 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: GO TO: Step 5 Intake Manifold Sensor -GX9-, CHECKING - 5 . -- NO: PERFORM: Visual Inspection of wiring and component. CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals. REPAIR: Faulty wiring or connector. GO TO: Step 5 Intake Manifold Sensor -GX9-, CHECKING - 5 .
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