Glass, Frames and Mechanisms — 2016 workshop reference 1231

K5 CHECK THE REAR WINDOW DEFROST RELAY

Ignition OFF. Carry out the rear window defrost relay component test. Refer to Wiring Diagrams Cell 149 for schematic and connector information.

Did the rear window defrost relay pass the component test?

Yes	REPAIR the open in the rear window defrost relay output circuit.
No	INSTALL a new rear window defrost relay.

K6 CHECK THE REAR WINDOW DEFROST RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE

Ignition OFF. Disconnect: FCIM C2402A. Ignition ON. Measure:

Positive Lead Measurement / Action Negative Lead Ground Rear Window Defrost Relay, socket pin 2

Original table alignment retained · Scroll horizontally if needed

Glass, Frames and Mechanisms — original illustration 1, reference 1231Original colors & callouts · Select to enlarge

Is any voltage present?

Yes	REPAIR the circuit.
No	GO to K7

K7 CHECK THE REAR WINDOW DEFROST RELAY CONTROL CIRCUIT FOR AN OPEN

Ignition OFF. Measure:

Positive Lead Measurement / Action Negative Lead C2402A-7 Rear Window Defrost Relay, socket pin 2

Original table alignment retained · Scroll horizontally if needed

Glass, Frames and Mechanisms — original illustration 2, reference 1231Original colors & callouts · Select to enlarge

Is the resistance less than 3 ohms?

Yes	GO to K8
No	REPAIR the circuit.

Source reference 1231

2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.