Manifold Absolute Pressure Sensor, Checking

Special tools and workshop equipment required 

• Multimeter.
• Wiring diagram.

Test conditions 

• TheMotronic Engine Control Module (ECM) -J623- OK.
• The parking brake must be applied, otherwise daytime running lights are switched on.
• On vehicles with automatic transmission, selector lever must be in position "P" or "N".
• The ground connections between engine and body must be OK.

Function test 

-- Connect the scan tool.

-- Turn the ignition to the ON position.

-- Using the scan tool, Check the specified value of the Manifold Absolute Pressure (MAP) Sensor -G71- ignition on, engine off:

Diagnostic text	Specified value
Intake manifold pressure	approx. 100 kPa

If the specified value was obtained:

-- Condition is not present at this time. Check connections for loose or damaged terminals and check harness for an intermittent short.

If the specified value was Not obtained:

Test sequence 

-- Disconnect the Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector.

-- Start the engine and run at idle speed.

-- Using a multimeter, check the Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector terminals 1 to 3 for voltage.

Specification: above 4.4 V

-- Using a multimeter, check the Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector terminals 1 to 4 for voltage.

Specification: above 4.8 V

-- Switch the ignition OFF.

If the specified values were obtained:

-- Replace Manifold Absolute Pressure (MAP) Sensor -G71-.

If the specified values were Not obtained:

Checking wiring 

-- Remove the Motronic Engine Control Module (ECM) -J623-. Refer to the Repair Service Information.

-- Using a multimeter, check the Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector to the Motronic Engine Control Module (ECM) -J623- electrical harness connector T60 for resistance. Refer to appropriate System Wiring Diagram Information for pin locations.

Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector terminal:	Engine Control Module (ECM) -J220- electrical harness connector T60 terminal:
1	13
3	44
4	56

Specified Value: 1.5 ohm max.

If the specified value was Not obtained:

-- Check the wiring for an open circuit, high resistance, short circuit to each other, Battery (+) or Ground.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

Specified value: 1.5 Ω max.

If no malfunction is detected in the wiring and the voltage supply was Not OK:

-- Replace the Motronic Engine Control Module (ECM) -J220-. Refer to the Repair Service Information.

Final procedures 

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .