Service manual

(125)
DC voltage should not be present between
terminals 85 and 87 on the relay when the
ignition key is disengaged. If voltage is present
at these terminals the relay is defective and
must be replaced.
Next, energize the vehicle’s ignition switch
and check for voltage between terminals 85
and 86 on the relay. Voltage should be present.
If no voltage is present between these
terminals, other components and connections
are suspect, such as the switch, thermostat or
circuit board.
As our final test of the relay, check for
voltage between terminal 85 and 87. If no
voltage is present the relay is defective and
must be replaced.
(128)
A defective 12 volt heating element will also
cause the refrigerator not to operate on the DC
mode. Disconnect the heater lead that attaches
to the 87 terminal on the DC relay and the
lead that attaches to the refrigerator grounding
strip.
A-6-42