Charge Air Pressure Sensor, Checking
Observe all safety precautions: SAFETY PRECAUTIONS
View clean working conditions: CLEAN WORKING CONDITIONS
Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.
For wiring diagrams, component locations, and connector views, Refer to the applicable SYSTEM WIRING diagram.
Special Tools And Workshop Equipment Required
- Multimeter
- Wiring diagram
Test requirements
- The Motronic Engine Control Module (ECM) - J623- fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- On vehicles with automatic transmission, selector lever in position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK
Start diagnosis
-- Remove the engine cover with air filter. Refer to appropriate service information.
Test sequence
-- Disconnect the Charge Air Pressure Sensor -G31- electrical harness connector -arrow-.
-- Start engine and let it run at idle.
-- Using a multimeter, check the Charge Air Pressure Sensor -G31- electrical harness connector terminals 1 to 3 for voltage.
Specified value: min. 4.5 V
-- Switch the ignition off.
If the specification was obtained:
-- Replace the Charge Air Pressure Sensor -G31-.
If the specification was not obtained:
Checking wiring
If the manufacturers test box is being used, perform the following step.
-- Install the test box.
If the manufacturers test box is not being used, perform the following step.
-- Remove the Motronic Engine Control Module (ECM) -J623-. Refer to appropriate service information.
-- Using a multimeter, check the Charge Air Pressure Sensor -G31- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J623- electrical harness connector T60 terminals for an open circuit according to wiring diagram.
| Charge Air Pressure Sensor -G31- electrical harness connector terminals | Motronic Engine Control Module (ECM) -J623- electrical connector T60 terminals or test box sockets |
|---|---|
| 1 | 13 |
| 3 | 27 |
| 4 | 23 |
| pin 2 is blank |
Specified value: 1.5 Ω max.
If the specification was not obtained:
-- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
-- If necessary, repair the faulty wiring connection.
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
If no malfunction is detected in the wiring and if the voltage supply was OK:
-- Replace the Charge Air Pressure Sensor -G31-.Refer to appropriate service information.
If no malfunction is detected in the wiring and if the voltage supply was not OK:
-- Replace the Motronic Engine Control Module (ECM) -J623-. Refer to appropriate service information.
-- Install the engine cover with air filter. Refer to appropriate service information.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .