Circuit City just installed a new Alpine head unit into my '91 Coupe. I can't get any AM reception. The previous owner had a pioneer head unit installed. It didn't receive AM either.

Any ideas? My forum search didn't turn up anything.

Thanks in advance.

Most likely the OEM setup was two antenna leads. One was AM/FM, the other was FM only. Take a look behind the radio for another antenna lead and swap them. I have the same problem with my 92 100. Two antenna leads with diversity ends and only one input on my aftermarket blaupunkt hu. The reception is not great with only one of the leads plugged in but I haven't been able to find a y-adapter for the two OEM leads.

Tried the Y adaptor - doesn't work either. I finally just installed a power antenna in the rear quarter/trunk and ran a lead to the dash.

Now AM and FM are nice and clear.

PS: I have an Alpine system too. Head unit, CD changer and amp but there are better speakers for the money than Alpine brand.