Suzuki Samurai 1986, Service Manual

Page: 184 / 482

[Checking sensors and their lead wires]
The sensors constituting the feed back system are; wide open micro switch, idle micro switch, thermal
switch, high altitude compensator, thermal engine room switch and fifth switch. If
any
of the above
sensors malfunctions or if the sensor circuit has some trouble, signals are not sent to the ECM and conse-
quently the feed back system will not function properly.
Therefore, check each sensor and its circuit according to the following procedure.
1) Turn OFF the ignition switch.
2) Disconnect the coupler from the ECM.
3) Connect the ohmmeter between the terminal of the disconnected coupler and the terminal
(ground) as shown in below figure and measure the resistance. And then repeat the same with each of
the terminals and
Coupler (Viewed from wire
harness side)
2. Wide open micro switch
3. idle micro switch
4. Thermal switch
5. Thermal engine room switch
6. Fifth switch
7. High altitude compensator
8. (Gray/Red) lead wire
9. (Gray/Yellow) lead wire
10. lead wire
11. P/B (Pink/Black) lead wire
12. (Gray/Black) lead wire
13. (Light green/Red) lead wire
14. B/G (Black/Green) lead wire
Fig. Checking sensors and their circuits
4) If each ohmmeter reading is as given below, the sensor and its circuit are in good condition. But if not,
the sensor itself may be defective or the lead wire disconnected or out of contact. After checking,
connect the coupler to ECM securely.
Idle micro switch
High altitude compensator
Thermal engine room switch
Wide open micro switch
F i f t h s w i t c h
Ohmmeter
reading
Condition
When coolant temp. is low.
When coolant temp. is above
When engine is warm and accelerator pedal is not depressed.
When accelerator pedal is depressed a little.
When altitude is below 1,220 m (4,000 ft.).
0 When altitude is above 1,220 m (4,000 ft.).
When temp. in engine room is low.
When temp. in engine room is above
(67°F).
0
When accelerator pedal is not depressed or depressed only a
little.
When accelerator pedal is depressed all the way.
When gear shift lever is shifted to low, second, third, forth or
reverse gear
position.
0 When gear shift lever is shifted to fifth gear position.
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