Detecting Breaks in Rear Window Defogger Grid
REAR WINDOW DEFOGGER GRIDTo detect breaks in the grid lines, the following procedure is required:
1. Turn the ignition switch to the On position. Press the rear defogger switch once. The indicator lamp should light. If OK, go to Step 2. If not OK, refer to the Windows and Glass/Heated Glass Element/Heated Glass Element Relay/Defogger Relay diagnosis.
2. Using a voltmeter, connect the negative lead to a good body ground. Place the positive lead on the vertical bus bar on the left side of the vehicle. The voltmeter should read battery voltage. If OK, go to Step 3. If not OK, go to Rear Window Defogger Relay Test.
3. With the negative lead of the voltmeter, contact a good body ground point. The voltage reading should not change. If OK, go to Step 4. If not OK, repair the circuit to ground as required.
4. Connect the negative lead of the voltmeter to the right side bus bar and touch each grid line at mid-point C with the positive lead. A reading of approximately six volts indicates a line is good. A reading of zero volts indicates a break in the grid line between mid-point C and the left side bus bar. A reading of 10-14 volts indicates a break between midpoint C and the right side bus bar. Move the positive lead on the grid line towards the break and the voltage reading will change as soon as the break is crossed.
GRID LINE AND TERMINAL REPAIR
WARNING: REPAIR KIT MAY CAUSE SKIN OR EYE IRRITATION. CONTAINS EPOXY RESIN AND AMINE TYPE HARDENER, HARMFUL IF SWALLOWED. AVOID CONTACT WITH SKIN AND EYES. FOR SKIN, WASH AFFECTED AREAS WITH SOAP AND WATER. DO NOT TAKE INTERNALLY. IF TAKEN INTERNALLY, INDUCE VOMITING; CALL A PHYSICIAN IMMEDIATELY. IF IN CONTACT WITH EYES, FLUSH WITH PLENTY OF WATER. USE WITH ADEQUATE VENTILATION. DO NOT USE NEAR FIRE OR FLAME. CONTENTS CONTAIN 3 PERCENT FLAMMABLE SOLVENTS. KEEP OUT OF REACH OF CHILDREN.
The repair of the grid lines or the terminal is possible using the Mopar Repair Package or equivalent.
1. Mask repair area so conductive epoxy can be extended onto the line or the bus bar.
2. Follow instructions in repair kit for preparing damaged area.
3. Remove package separator clamp and mix plastic conductive epoxy thoroughly. Fold in half and cut center corner to dispense epoxy.
4. For grid line, mark off area to be repaired with masking tape or a template.
5. Apply conductive epoxy through slit in masking tape. Overlap both ends of the break by 19 mm (3/4 inch).
6. For a terminal or pigtail replacement, mask adjacent areas so epoxy can be extended onto line as well as bus bar. Apply a thin layer of epoxy to area where terminal was fastened and to adjacent line.
7. Apply a thin layer of conductive epoxy on terminal and place terminal on desired location. To prevent terminal from moving while the epoxy is curing, it must be wedged or clamped.
8. Carefully remove masking tape from grid line.
CAUTION: Do not allow the glass surface to exceed 204 °C (4000 °F), glass may fracture.
9. Allow epoxy to cure 24 hours at room temperature or use heat gun with a 2600 to 3710 °C (5000 to 700 °F) range for 15 minutes. Hold gun approximately 254 mm (10 inches) from repaired area.
10. After conductive epoxy is properly cured remove wedge from terminal and check out operation of rear window defogger. Do not attach connectors until curing is complete.