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Coolant Temperature Switch Circuit

Fig. 4 Control Unit Electrical Connector Terminal Identification.:






1. With ignition switch in the On position, check voltage between terminal 10 and ground, Fig. 4.
2. With engine temperature below 77 deg F voltage should read 0-1 volt.
3. With engine temperature above 86 deg F voltage should read 10-14 volt.
4. If voltage is not as specified, check circuit and connectors.
5. If circuit is satisfactory, replace coolant temperature switch.