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SEF348N
+When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
+Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the
ECM's transistor. Use a ground other than ECM terminals,
such as the ground.
+Install the break-out box between ECM and ECM harness
connectors when measuring ECM input/output voltage.
Wiring Diagrams and Trouble DiagnosisNJEC0604When you read Wiring diagrams, refer to the following:
+GI-12, ªHOW TO READ WIRING DIAGRAMSº
+EL-10, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
+GI-32, ªHOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSESº
+GI-21, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
PRECAUTIONSYD
Precautions (Cont'd)
EC-497
Page 794 of 2493
Special Service ToolsNJEC0605
Tool number
Tool nameDescription
KV111060S0
Removal/Installation tool
kit for fuel injection pump
NT814
KV109E0010
Break-out box
NT825
KV109E0050
Y-cable adapter
NT826
PREPARATIONYD
Special Service Tools
EC-498
Page 795 of 2493
Engine Control Component Parts LocationNJEC0607For more details of ECM location, refer to ªELECTRICAL UNIT LOCATIONº in EL section (EL-319).
NEF396A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
Engine Control Component Parts Location
EC-499
Page 796 of 2493
SEF894Y
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
Engine Control Component Parts Location (Cont'd)
EC-500
Page 797 of 2493
NEF376A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
Engine Control Component Parts Location (Cont'd)
EC-501
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Circuit DiagramNJEC0608
NEF397A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
Circuit Diagram
EC-502
Page 799 of 2493
System DiagramNJEC0609
NEF398A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
System Diagram
EC-503
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System ChartNJEC0611
Input (Sensor) ECM Function Output (Actuator)
+Electronic control fuel injection pump
+Crankshaft position sensor (TDC)
+Engine coolant temperature sensor
+Accelerator position sensor
+Accelerator position switch
+Park/Neutral position (PNP) switch*
+Ignition switch
+Battery voltage
+Vehicle speed sensor
+Air conditioner switch
+Mass air flow sensor
+Stop lamp switchFuel injection controlElectronic control fuel injection
pump
Fuel injection timing controlElectronic control fuel injection
pump
Fuel cut controlElectronic control fuel injection
pump
Glow control system Glow relay & glow lamp
On board diagnostic system MI (On the instrument panel)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Air conditioning cut control Air conditioner relay
*: If so equipped
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
System Chart
EC-504