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Trouble Shooting - Engine Idling

TROUBLE SHOOTING - ENGINE IDLING

On-Off Ratio % Readout Malfunction Test Step
0 Ground connector socket No. 2 open. Open ckt in wire to socket No. 3 or No. 6 of diagnostic socket or on-off ratio tester defective. Mixture adjustment too rich. Repair as necessary
10 Airflow sensor position indicator polarity reversed or defective. Terminals of throttle valve switch polarity reversed or defective. Terminals of throttle valve switch connector (idle and full load contacts reversed or idle contact open with microswitch closed. 7.0-7.6, 5.0-5.3, 10.0-10.3, Repair as necessary
20 Full load contact defective or throttle valve switch polarity reversed. 20% displayed only with activated microswitch 5.0-5.3, Repair as necessary
30 Short or open ckt between CIS-E control unit and coolant temperature sensor or defective coolant temperature sensor, or excessive deviation in temperature values in comparison with EZL ignition control unit 6.0-6.3, Repair as necessary
40 Open or short in airflow sensor position indicator wiring or defective airflow sensor position indicator 7.0-7.6
50 O2 sensor not operational/defective, open ckt Repair as necessary
60 Unlikely speed signal at CIS-E control unit 11.0-11.2
70 Unlikely TNA-signal (RPM) at CIS-E control unit 8.0-8.1
80 Interrupted data exchange between EZL ignition control unit & CIS-E control unit 12.0
90 Unlikely current reading at EHA 4.0-4.4
95 Decel fuel shut-off valve in operation N/A
100 No voltage or ground at CIS-E control unit No voltage or ground at CIS-E control unit CIS-E control unit defective On-off ratio tester defective. Lambda adjustment too lean. O2 sensor defective (short to ground) Test Step 1.0-3.0, 14.0-14.7
Oscillates No malfunctions of the signals monitored N/A
COOLANT TEMPERATURE SENSOR SPECIFICATIONS

°F (°C) Ohms Volts at Socket
-4 (-20) 15,700 3.24 - 3.94
14 (-10) 9200 2.84 - 3.47
32 (0) 5900 2.39 - 2.93
50 (10) 3700 1.94 - 2.37
68 (20) 2500 1.51 - 1.84
86 (30) 1700 1.16 - 1.42
104 (40) 1180 0.88 - 1.08
122 (50) 840 0.66 - 0.80
140 (60) 600 0.50 - 0.61
158 (70) 435 0.38 - 0.46
176 (80) 325 0.29 - 0.35
194 (90) 247 0.22 - 0.26