d) Pull off wires from coolant temperature sending unit in engine compartment (large plug connection).
(Don't let plug contact ground,)
Test lamp should go out.
e) Program control in OFF position.
Test lamp should come on.
Note: If the above tests shows a defect, which can't be found in control switch or wiring, check the control unit as follows.
Connect test lamp on connected plug (S2) term. 3 (brown) and term. 10 (green).
Set selector lever to AUTOM or BI.
Test lamp should come on at coolant temp, above 10 4° F. Test lamp should go out at coolant temp, below 104° F.
(Pull off coolant temperature sending unit wires on warm engine.)
If selector lever is set at "OFF",ground rail of solenoid valve should be connected to ground. If not, cold over-ride relay in control switch is not working.
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