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System Diagnosis

The EDS can be tested by a built-in test program to EDS control unit. Fault signals can be found by connecting an On-Off Ratio Tester (909-589-00-21-00) into EDS system test connector. The number of times needle oscillates on tester shows which electric component is faulty or which components of EGR circuit are defective. The EDS control unit is located on right front footwell behind side kick panel. See EDS SYSTEM DIAGNOSIS 

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EDS SYSTEM DIAGNOSIS

Number of Needle Oscillations Component/Circuit Not Functioning
1 RPM Sensor
2 Fuel Rack Sensor
3 Air Flow Sensor
4 Altitude Correction Capsule
5 (1) EGR Circuit
5
A) EGR Valve
B) Vacuum Transducer
C) Airflow Sensor
D) Air Recirculating Valve
E) Vacuum Transducer
8 Coolant Temperature Sensor
9 Air Temperature Sensor
10 Reference Resistor
11 Trimming Plug
(1) Reading only at 1200 RPM for 5 seconds.