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On/Off Ratio Identification

LH-SFI CONTROL UNIT ON/OFF RATIO ID (IGNITION ON, ENGINE OFF)

On/Off Ratio Malfunctioning Component/System
0 (1) Open Ckt In Voltage Supply From Diagnostic Connector Terminal No. 3
10 Idle Speed Recognition Inactive
20 Full Load Recognition Inactive
30 Coolant Temp. Less Than 158°F (70°C) Or Greater Than 230°F (110°C)
40 Not Used
50 Input Signals Okay (No Malfunctions)
60 TN (RPM) Signal Or Camshaft Position Sensor Not Present While Starting
70 Starter Engaged
80 Controller Area Network (CAN) Defective
90 Fuel Safety Shutoff Active
(1) Diagnostic connector is located in right rear corner of engine compartment.
LH-SFI CONTROL UNIT ON/OFF RATIO ID (ENGINE IDLING)

On/Off Ratio Malfunctioning Component/System
0 Short Circuit To Battery Positive In Wire For Test Connection (Diagnostic Connector Terminal No. 3)
10 Idle Speed Recognition Applied Constantly Output Of Fuel Injectors Or One Or More Fuel Injectors Has An Open Circuit
30 Coolant Temperature Sensor
40 Air Mass Sensor Hot-Wire
50 (1) Oxygen Sensor Not Operational Or Defective
60 Camshaft Position Sensor
70 TN (RPM) Signal
80 Controller Area Network (CAN) Defective
90 Vehicle Speed Signal
95 (2) Deceleration Fuel Shutoff Active
100 No Voltage At LH-SFI control unit.
(1) If needle oscillates on on/off ratio tester, all monitored signals are okay.
(2) No malfunction is indicated. LH-SFI control unit is in deceleration fuel shutoff mode.