There are actually a few things that will cause this problem. Trying to type out every test for you to try is not practical. What I can do is upload the service manual for your retrival and then with it in hand and a few basic tools you can run the diagnostics yourself. Even if you can not do these tests you can save a bunch of money and hire a good handyperson at half the cost of a service tech.
Please click here for the file. If you get stuck please let me know.
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OK I'll read the manual and try.
If you have any questions about the manual please post them here.
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