WASTEGATE Bypass Regulator Valve - N75-, Checking

General Description

Both the boost and intake pressures are used to control the wastegate of the turbocharger. These pressure signals are supplied to the Engine/Motor Control Module -J623-, which then sends a pulse-width modulated signal to the Wastegate Bypass Regulator Valve -N75-. As a result, the Wastegate Bypass Regulator Valve -N75- controls the vacuum supply to the pressure unit, which directly acts on the wastegate via a connecting rod. This control system regulates the turbine speed and sets the maximum boost pressure.

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 automatic transmission, ensure the selector lever position is in "P".
Vehicles with manual transmission, ensure the shifter lever position is in "N" with the 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. -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Wastegate Bypass Regulator Valve -N75- harness connector. CHECK: Wastegate Bypass Regulator Valve -N75- component connector terminals 1 to 2 for resistance. SPECIFIED VALUE: 5 - 25 Ω (@ approx. 20° C). -- Was Value obtained?	-- YES: GO TO: Step 3. -- NO: REPLACE: Wastegate Bypass Regulator Valve -N75-. Refer to appropriate Service Information. GO TO: Step 5.
3	IGNITION: ON. CHECK: Wastegate Bypass Regulator Valve -N75- harness connector terminal 1 to ground for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery voltage. -- Was Value obtained?	-- YES: GO TO: Step 4. -- 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.
4	REMOVE: Engine/Motor Control Module -J623-. Refer to appropriate Service Information. CHECK: Wastegate Bypass Regulator Valve -N75- harness connector terminal 2 to the Engine/Motor Control Module -J623- harness connector T56d / 54 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: TIP: The Wastegate Bypass Regulator Valve -N75- may fail under loaded operation; please swap a known good Wastegate Bypass Regulator Valve -N75- prior to continuing to the next step. GO TO: Step 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.
5	Final Procedure Perform a road test to verify repair. -- Does the original DTC return?	-- YES: CHECK: Engine/Motor Control Module -J623- harness connector for any damaged, pushed-out pins. REPAIR: As necessary. If all electrical connections are OK: REPLACE: Engine/Motor Control Module -J623-. Refer to appropriate Service Information. Clear the DTC's. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY . Repair is complete. Generate Readiness Code. Refer to READINESS CODE . Return vehicle to Customer. -- NO: Perform the diagnostic procedure for any DTC's. If no DTC's return, the repair is complete. Return vehicle to customer.