How is the antenna connected to the radio then?

Here's another:
https://www.chevyhhr.net/forums/%22h...hlight=antenna

 

There is probably a harness up there, it's just not near the visor screws.

 

Still looking for suggestions....

The link posted here about the TSB, actually ends with someone else having the same exact issue as me and going unanswered as well.

 

I wonder if the antenna lead is loose in the head unit(or wherever it is)? This thread has a lot of information, maybe something there that will help.

 

I have an issue with my 2008 HHR similar to the OP's. The radio works fine all the time for local driving. Whenever I'm on a trip, after a while it cuts out and I can only receive the strongest AM or FM stations (usually none). This seems to happen based on the time the vehicle is being driven. It does not seem dependent on outside ambient temperatures. Also, it doesn't seem to depend on whether the radio was on or off, just how long the car has been driven. The CD always works. I'm convinced it is something related to the powered antenna but not sure how to mitigate it. It will not regain reception while driving. ie, once it cuts off, the vehicle needs to be shut down for a period before it starts working again, so it's not an on/off/on/off issue.
The radio is the base model OEM and no upgrades or changes from factory install. I've owned the vehicle since new and nothing was ever modified on it.
Any ideas?

 

It couldn't have anything to do with distance from the station?

There are plenty of posts about the antenna amp. I don't recall this particular one, so how is it similar to the OP?

There are 3 possible radios. What code is on the label on the glove box door, UW5, UQ3 or U2K?

 

It's an LS with no options. I don't think the model of radio has anything to do with it. I normally can pull in about 50 FM stations, so no, it's in no way related to distance from the station other than if I'm really really close to the transmitter tower, it'll pick up a signal. Also, I can pick up an AM station under the same conditions from time to time. I'm absolutely convinced it's an antenna issue but just don't know how to resolve it. I read a number of threads on here regarding reception problems but there doesn't seem to be a "solution" per se. This problem wasn't original to the car, it was fine for several years but has more recently developed the problem.

 

I looked in the glove box door and there's over 40 3 letter codes. I have no idea which on refers to the radio.

 

Do any of those 3 letter codes match any of the codes that donbrew provided?

 

The wiring is different, thus the question.

I'm less interested than you.