Code 3-1-2 (Knock/Fuel Enrichment)

Turn ignition on. Connect a voltmeter between terminal No. 28 (Brown/White wire on 240 and 240 DL; Gray/Red wire on 740 GL with Bosch EFI) of fuel system ECU connector and ground. Reading should be approximately 0.7 volt. If voltage is not specified, check resistance between appropriate ECU connector wire and knock sensor. For knock sensor testing, see SYSTEM/COMP TESTS article.