Rear Defroster = Horrible Radio Static????

[jp233]

there is a TSB out for the wagons, where they add an additional ground strap and stuff.

 

go to http://thel7.com/ and find the TSB and check it out, it may help you if you're outside warranty

[SVXdc]

Thanks for the link. That site is a nice resource.

 

The AM reception / tailgate issue is this one: #15-115-05 AM Band Radio Noise (dated 5/4/2005)

[Rick D.]

Wow, that's a great resource! Thanks for the lead. I think my ground is OK, but I'm going to check it right now.

[Rick D.]

.... I took off the ground connections and brightened them up but no change. Checking the ground seemed to be a logical step. I can't figure out how changing the back glass fixes things because barring an internal failure that should show, all it is is wire embedded in glass. That would be a pricey step. I am leery of trusting the dealer with this since I would hate to have them just throw parts at the problem without adequate testing. I'm going to hunt some other forums too. This can't be just a Subaru problem.

[Rick D.]

Well, OK I found the same issue with Lexus, Corvette and Mercedes. My frustration now is that I don't know how to better trouble shoot the failure. I sure don't want to pay the dealer guys to trace it. Still can't figure how to test the embedded antenna. Someone suggested continuity check. Comment? Only problem is I wouldn't know what value is OK and what isn't.

[SVXdc]

If you can find the repair manual, there's a diagnostic procedure under Body > Entertainment > Antenna. Fairly brief, but may still help a little. The sections after that are Antenna Amp. and Noise Suppressor.

 

In the mean time, the vacation pics include some nice rear antennas. The ones from 2005 are similar to 2006.

[Rick D.]

OK, since my last post, I double checked myself by running a battery jumper cable from the battery ground to the hatch. No improvement. I purchased a rubber ducky antenna and grounded it and touched the amplifier output leads at the window glass antenna. I can get some gain and barely hear the AM sound, but it made a difference. No difference on FM. I inspected all the window elements and can find no breaks. I tried testing the continuity with my ohm tester but not sure if I knew what I was doing. I then wondered if maybe the power to the amplifier was bad. I checked the manual, but it was a waste. No mention of fusing. I gotta believe its fused somewhere. Maybe it's sistered into another circuit? Anyhow everything else works. No fuse problems I could see. Now I'm wondering if I can check to see that I am getting 12 volts to the amp. I should be able to check that if I attach a REALLY small extension to my probe to get inside the connector. That's my next step. Any ideas, please step up to the plate. I'm not ready to throw parts at this... an $80 amp was quite enough!

[DiscoPete]

Yes, you could get a voltage measurement by using a small wire to probe the connector or even a small straight pin to probe through the insulation if you are careful not to break the conductor strands.

 

Since you already have a rubber ducky antenna, would it be possible to plug it directly into the radio to see if it gets good reception that way? Maybe try plugging the antenna into the end of the antenna cable where the amplifier connects. There should be very little loss from the far end of the antenna coaxial cable into the radio, even without the amplifier. (I suspect that the amplifier is there mostly to overcome the deficiencies of the in-glass antenna).

 

Maybe a bad ground is at the radio end of the cable? Hard to tell without checking. Even the same symptom might have different causes in different cars. Good luck.

[DiscoPete]

OK, since my last post, I double checked myself by running a battery jumper cable from the battery ground to the hatch. No improvement. I purchased a rubber ducky antenna and grounded it and touched the amplifier output leads at the window glass antenna. I can get some gain and barely hear the AM sound, but it made a difference. No difference on FM. I inspected all the window elements and can find no breaks. I tried testing the continuity with my ohm tester but not sure if I knew what I was doing. I then wondered if maybe the power to the amplifier was bad. I checked the manual, but it was a waste. No mention of fusing. I gotta believe its fused somewhere. Maybe it's sistered into another circuit? Anyhow everything else works. No fuse problems I could see. Now I'm wondering if I can check to see that I am getting 12 volts to the amp. I should be able to check that if I attach a REALLY small extension to my probe to get inside the connector. That's my next step. Any ideas, please step up to the plate. I'm not ready to throw parts at this... an $80 amp was quite enough!

 

 

There is a Subaru Service Bulletin # 15-126-07, issued 02/13/08 describing how to test for the problem.

 

It says to turn on your car radio and the rear defroster to verify the problem. Then use a portable radio tuned to the same station and moved around next to the rear glass to see if you can find the break in the grid that is generating the radio noise. It may be necessary to conduct the test away from other sources of radio interference such as florescent lamps, high voltage power lines, thunderstorms, etc.

 

The break in the defroster grid may be so small that a magnifier will be needed to see it.

 

If you find a break in the grid, repair it with the Permatex Quick Grid Rear Window Defogger Repair Kit, Part # 15067, available at local auto parts stores. A successful repair will read zero ohms.

[RJS5689]

Great, just noticed my car is doing this now too. Oh well, I have tints on my window and I'm not paying to have my rear window re-tinted after my glass is replaced.

[apexi]

I've had this happen on a few vehicles i've owned. The problem I have with my legacy is that when I'm charging a device with the cigarette lighter, it causes my radio reception to go down the tubes. It seems like it only happens with stations where the tower is more than 30 minutes away.

[shutterbc]

I have a similar issue though now it seems it's just as bad when the defroster is off. AM reception is almost totally gone now. Looks like the TSB links aren't working anymore by the way.

 

Thanks for posting the test procedure in the forum

[hadvw]

Having a similar issue.. AM reception totally died, FM is really weak.

 

Here's what I found: if I tune to a known good AM station, crank it up, and touch the traces of the antenna with my fingers, I get some reception.

 

Used a multimeter to test ever trace I could think of and they were all 0.

 

Any idea where the wiring for the antenna runs??

[Rick D.]

I found, after a lot of checks and grounding work, my antenna wire was broken under the flexible cover connecting the (wagon) hatch to the pillar. You need to pry off the trim cover on the left rear pillar also. I spliced in a heavier gauge wire with more length to ward off This was a PITA to trouble shoot because the break was not clean; sometimes it worked and sometimes not until it broke entirely.

 

BTW, I want to thank the members of this forum for all their contributions to this and other subjects. This fix sure beat paying a grand to the dealer to fight the problem and probably replace god-knows-what.

[NJLGT]

My dad's LGT had this problem, they replaced the rear glass under warrenty... something with the interference between defroster strips in the rear glass and the internal antenna

[hadvw]

I found, after a lot of checks and grounding work, my antenna wire was broken under the flexible cover connecting the (wagon) hatch to the pillar. You need to pry off the trim cover on the left rear pillar also. I spliced in a heavier gauge wire with more length to ward off This was a PITA to trouble shoot because the break was not clean; sometimes it worked and sometimes not until it broke entirely.

 

Ok, so you're saying DRIVER's side rear pillar? How much trim did you have to remove in total? So far, I've only removed the little 4x4" square in the hatch itself..

 

Definitely want to give this one more try before ripping apart the dash to get to the stereo...

[Rick D.]

I removed the hatch trim, the upper trim piece and the left (driver's) side as well as the one ln the left rear pillar. Then I muscled the plastic flex conduit between the hatch and pillar. All this was by hand. I found the break (s) right at the conduit. Hope this makes sense. Good luck!

[hadvw]

I removed the hatch trim, the upper trim piece and the left (driver's) side as well as the one ln the left rear pillar. Then I muscled the plastic flex conduit between the hatch and pillar. All this was by hand. I found the break (s) right at the conduit. Hope this makes sense. Good luck!

 

Thanks. I'm sure it will make sense when I go back to work on it (once the rain stops!)

[Mindspin311]

I've had this happen on a few vehicles i've owned. The problem I have with my legacy is that when I'm charging a device with the cigarette lighter, it causes my radio reception to go down the tubes. It seems like it only happens with stations where the tower is more than 30 minutes away.

 

This happens to me a lot. Plug in my cellphone and I have to switch to CD because every station has static.

[massdrewski]

13/08 All models Radio static when the radio and rear window defogger are on at the same time, Customer complaint of radio static when the radio and rear window defogger are on at the same time, there is the possibility of a break in one or more of the defogger grids. When the grid is broken, a high resistance field is created at the break point which can create static on some radio stations. The level of resistance is usually high enough to create a field of interference which projects out from the glass. The break can be detected visually or by using a portable radio.

Using a portable radio, set the radio to the same frequency and station being disturbed by static. From the outside of the vehicle, slowly move the radio’s antenna across the defogger grids. When interference is encountered, inspect that specific area closely for a break. Depending upon the size of the break, a magnifying glass and/or eyeloupe may be required.

Once the break is identified, it should be repaired using the Permatex® repair kit instead of replacing the rear glass. Note: Make sure to carefully read and follow the instructions

and precautions that are included with the Permatex® repair kit.

Permatex® Quick Grid™ Rear Window Defogger Repair Kit, part # 15067, used for repairing damaged rear window defogger grids, is available at local automotive parts stores.

[White Knight]

Our car is 4 day's old and just this morning my wife puts on the defroster and she got interference with the radio... I will have to run this test to see if that is what happened to my car.

[Mindspin311]

So is there any sort of TSB for this?

[DiscoPete]

Yes. It is Subaru Service Bulletin #15-126-07, from February 13, 2008.

 

A couple of posts in this thread mention a procedure that involves moving a small portable radio around the defroster grid while it is generating radio noise, to pinpoint the location of the crack in the grid element that is generating the interference and then using a Permetex repair kit to fix it. Those instructions are repeats of what is in the service bulletin.

[Mindspin311]

So its something they will def. fix for free..

[Lgt005]

So does that mean Subaru will repair this for free? I have this issue and my fm reception is horrible. I don’t know if our cars are to old at this point.