LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volvo >> 1992 >> 240 GL, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Self-Diagnostics - Fuel Injection >> Control Function No. 3 >> Testing Fuel System Components
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Testing Fuel System Components

  1. Turn ignition on. Locate diagnostic unit, and remove its cover. Connect selector cable to socket No. 2. Depress push button 3 times. Each time button is depressed, hold it for more than 1 second and less than 3 seconds. While LED flashes, fuel injectors and idle valve should operate. Check by listening or feeling component when it is activated. If injectors fail to operate and LED flashes, go to step 2). If idle valve fails to operate and LED flashes, go to step 3).
  2. To test fuel injector circuit, connect an ohmmeter between harness side of fuel system ECU connector terminals No. 9 (Orange wire on 240; Blue/Yellow wire on 740/940) and No. 18 (Green/White wire on 240; Gray wire on 740/940). Resistance should be 4 ohms.
  3. If resistance is 5.3 ohms, one injector or wire to it is faulty. If resistance is 8.0 ohms, 2 injectors or wires to them are faulty. If resistance is 16 ohms, 3 injectors or wires to them are faulty. If resistance is incorrect, remove each injector connector. Each injector connector should have 16 ohms resistance. Repair as required.
  4. To test idle valve circuit, connect an ohmmeter between fuel system ECU connector terminals No. 33 (Green/Red wire on 240; Red/Black wire on 740/940) and No. 9 (Orange wire on 240; Blue/Yellow wire on 740/940). Resistance should be 8 ohms. If resistance is not as specified, check wiring and connections between idle valve and ECU. If wiring is okay, check idle valve. See IDLE AIR CONTROL VALVE in procedures in SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE Section.
scientia non olet · About LEMON Manuals