jayc67

Quick question please.

My '87 stopped playing out of the rear speakers but there is still voltage from the amp going to the speakers so I don't think it's the amp, and the speakers "click" when I turn the radio on.

The radio has a L/R balance **** but is there a hidden F/R fader control somewhere? I'm hoping I've simply moved something accidentally rather than lost the rear outputs from the radio.

The radio does "something" if I pull out the volume **** and turn it, there are 2 detents when I do this. Anyone know what that does?

I can't find a manual anywhere

Thanks for helping with a silly question.

StratfordShark

Is that the Toronto head unit? I sold one recently (never had a manual either) that came with my old 88 S4. That unit didn't have a fader - I think that was rare on older head units. When you say "voltage" from the amp have you checked that you're actually getting an ac signal? What are you measuring it with?

If you can get hold of a simple tone generator then test the rear speakers by putting signal directly to them after removing the big concave covers they're mounted on so that you have access to the speaker terminals. If you can't use a tone generator then using wires from a 1.5V cell see if you can make speakers click, but if they click when radio turned on they're probably ok.

If the speakers are working then it does sound as if there's fault in the rear channel.

jayc67

Thanks. I didn't think it had a fader, was just a hope.

No I haven't tried to see what the signal is, just put a voltmeter on the amp to see what it was putting out. Getting the same on front and back. Speakers are good, I plugged the rear speakers into the front amp output and they play fine so it's not wiring or speakers.

Just trying to figure out of it's the head or the amp. I'll try to borrow an o-scope from a friend of mine next week I guess and try to dig further into it.

Thanks.

inactiveuser1

On the 87 s4 stock radio the volumn button pulls out some.When pulling it straight out and keeping it out toward you turn at the same time to left for front and right for rear.Sometimes mine acts up and left side cuts out it works when it likes too.
Years ago a place sold me a short cable between the radio and the amplifier and that solved my problem.Years later it did the same but where I bought the cable they said it was no longer available.
That volumn **** pulled out and turned that is the fader.
When turning it slow you will feel it hit the middle area.
The little tab that flips up and down on the volumn **** left side area is for the amplifier.