OK – my defroster is fixed and working now. Hopefully, this information will help others that find they have this same problem. I would like this to be good information and am looking for feedback on how it can be improved.
First thing to say, if you are at the stage that your wire has broken from the clip, but the tab is still soldered to the glass – the repair is much more straightforward if you can get the clip off without pulling the copper tab off the glass – see posts above.
Here are the products from Frost Fighter that can be used to make the repair.
I ended up re-using my old copper tab so I did not need the TAB repair kit (red top). In fact, if you didn’t pull the copper tab off the glass, all you need is the UNI-CLIP (purple top). I ordered these direct from Frost Fighter and they shipped them right to my door.
The repair steps will include:
1. Get to the repair area.
2. Attach new clip to the power wire
3. Epoxy the old tab to the glass
4. Close up the repair area.
There are a bunch of very good pictures of tailgates and defrosters in the other threads on the site. I’ve got several more to add to the collective body of knowledge.
Step 1 – Get to the repair area.
I started getting to the repair area by opening the tailgate and then removing the cover. IIRC my cover had 10 screws to remove, once the cover is off, I removed the vapor barrier.
Next I needed to close the driver side latches of the tailgate, so that I could operate the window. It is pretty easy to do, just pinch down on the latches till they click.
Here is what the latches look like when they are closed.
Next I closed the window, just enough so that the repair area was exposed and available. Here is what mine looked like:
Step 2 – Attach the new clip to the power wire
The new clip needs to go on the end of this wire, right here:
I used a wire stripper to expose about ¼” of the wire. Next I slid the wire into the clip and crimped it down for a tight connection. The new clip installed looks like this:
Step 3 – Epoxy the old tab to the glass
The detailed workings of the defroster have been covered in other write-ups, but there a few aspects of basic principles that are appropriate to go over here again – because they have an impact on the quality of the repair. The electricity from the battery needs to get to the defroster wires painted and baked into the back window for the defroster to be able to heat up the glass. Electricity works best when moving through cleanly connected components, i.e. fuses, switches, wires, connectors and clips. Therefore, it is critical to prepare the surfaces to be connected properly.
I prepared the window by lightly sanding the area where the tab attached. The objective here is to expose clean silver, not remove the silver and get to glass.
I prepared the tab the same way, lightly sanding it until I got to shiny copper. Sorry about the picture quality – trust me it looked good.
The next thing to do is mask off a small square that I would be putting the clip in. This could be considered an optional step, but I found is helpful in two respects; first it slowed me down enough to make sure I oriented the clip correctly, second the tape built up a small wall to “float” the epoxy covered tab in while attaching it. Here is a close-up of the masked off area (I’ll explain the thermometer below)
The epoxy is a two part mixture that has additives in it that allow it to conduct electricity. The epoxy needs to be mixed in equal amounts, if it is not it will not harden and set up. The epoxy I used came pre-loaded into syringes, there was much more epoxy in the syringe than would be needed. So I decided to use about ½ of each syringe, to get equal amounts I marked the syringe plungers at the mid-way points.
Before mixing the epoxy, I put a small space heater in place to blow hot air on the repair area. The curing temperature for the epoxy is 70 degrees F. This being the middle of winter, even working in my garage it was not near 70. However, with the heater, the temperature of my repair area was over 120 degrees F – plenty good enough. The heater set up looked like this:
Mixing the epoxy, putting it on the tab and placing the tab in the masked off square in the proper orientation went pretty quickly. It went so quickly I didn’t snap any pictures.
Using the marks on my syringe, I put equal parts of epoxy on the mixing card. Using the mixing stick, I worked the two parts together for about a minute.
Next, I coated the tab with epoxy and placed it into the taped off square and floated it around to get the epoxy all over. I then took some of the epoxy remaining on the mixing card and added it to the area to build up and spread out the repair. I had to work quickly because the epoxy starts to set up in a couple of minutes at these high temps.
With the tab now in place, after about 20 minutes, I removed the masking tape. I then let the epoxy cure for a couple of hours. I kept the mixing card next to the repair area, so that I could use it to check the status of the epoxy cure without having to touch the repair.
Finally, after the epoxy had cured, I connected the tab to the clip.
Step 4 – Close up the repair area
The first step in closing up the repair area is to open the window.
After this, I put back the vapor barrier and cover panel.
Before closing the tail gate, I had to open the driver side latches. I found this was easiest to do by closing the tailgate enough to bring the latches in contact with the striker bolt and then using the handle to open the latches.
Finally I closed the tailgate and closed the window.
I did all this on Saturday, but did not get a chance to really test it until this morning, as you can see from the defroster lines, my defroster now works.