Manifold Absolute Pressure Sensor, Checking

Special Tools And Workshop Equipment Required 

• Multimeter.
• Wiring diagram.

Test Conditions 

• The Engine Control Module (ECM) -J220- 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.

-- Start engine and let it run at idle.

-- Using the scan tool, Check the specified value of the Manifold Absolute Pressure (MAP) Sensor -G71- at idle:

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 Engine Control Module (ECM) -J220-.

-- Using a multimeter, check the Manifold Absolute Pressure (MAP) Sensor -G71- electrical harness connector to the Engine Control Module (ECM) -J220- electrical harness connector T60 for resistance. Refer to Appropriate System Diagrams 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-.

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 .