Turbocharger Recirculating Valve - N249-, Checking

General Description

A Turbocharger Recirculation Valve -N249- keeps a portion of air running through the intake side of the turbocharger when the throttle valve is closed and boost pressure is still present. This keeps the turbocharger impeller from slowing down, reducing turbo lag when the throttle is applied again.

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 Turbocharger Recirculating Valve - N249-, CHECKING => 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Turbocharger Recirculation Valve -N249- harness connector. CHECK: Turbocharger Recirculation Valve -N249- component connector terminals 1 to 2 for resistance. SPECIFIED VALUE: 3 - 15 Ω (@ approx. 20° C). -- Was Value obtained?	-- YES: GO TO: Step 3 Turbocharger Recirculating Valve - N249-, CHECKING => 3 . -- NO: REPLACE: Turbocharger Recirculation Valve -N249-. Refer to appropriate repair information. GO TO: Step 5 Turbocharger Recirculating Valve - N249-, CHECKING => 5 .
3	IGNITION: ON. CHECK: Turbocharger Recirculation Valve -N249- harness connector terminal 1 to ground for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery voltage. -- Was Value obtained?	-- YES: GO TO: Step 4 Turbocharger Recirculating Valve - N249-, CHECKING => 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 Turbocharger Recirculating Valve - N249-, CHECKING => 5 .
4	REMOVE: Engine Control Module - J623-. Refer to appropriate repair information. CHECK: Turbocharger Recirculation Valve -N249- harness connector terminal 2 to the Engine Control Module - J623- harness connector T60 / 50 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: TIP: The Turbocharger Recirculation Valve -N249- may fail under loaded operation; please swap a known good Turbocharger Recirculation Valve -N249- prior to continuing to the next step. GO TO: Step 5 Turbocharger Recirculating Valve - N249-, 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 Turbocharger Recirculating Valve - N249-, CHECKING => 5 .
5	Final Procedure Perform a road test to verify repair. -- Does the original DTC return?	-- YES: CHECK: Engine Control Module -J623- harness connector for any damaged, pushed-out pins. REPAIR: As necessary. If all electrical connections are OK: REPLACE: Engine Control Module -J623-. Refer to appropriate repair 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.