88-94 Radio Issues

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DerekTheGreat

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I think that whine was a standard feature of all GM radios of that era.

Ken

What got rid of my audible tachometer was to add an additional ground from the two ground wires that come from the equalizer to the brainbox above the accelerator to the big bracket for the steering column. No more speaker tach after that.
 

kenh

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What got rid of my audible tachometer was to add an additional ground from the two ground wires that come from the equalizer to the brainbox above the accelerator to the big bracket for the steering column. No more speaker tach after that.

Thinking out loud here..... Or maybe just make sure all the existing grounds are squeaky clean????

Ken
 

highwaystar

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Didn't see this model no. listed. My oem cassette/equalizer model no. is 16191455. Build date: July 28, 1994. Just sent it off to be refurbished. This is out of a 1994 C1500 2wd.
 

John Hendrix

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If your interested... Retromanufacturing.com

They are now manufacturing a premium head unit that installs in the factory location.

2 different models. The SC-M2 and the SC-M4. Both have Bluetooth built in, clock, USB ports, auxiliary ports and pre amp outputs.
The M4 is IPhone/IPod compatible and has sub woofer outputs.

The downside is I do not believe they are compatible with the equalizer. But I am not sure. These head units are available from LMC, Crutchfield or directly from Retro manufacturing.

I just ordered the M4 for my 1993 K1500. I also picked up a used center vent with a storage cubby to replace the aftermarket head unit currently installed.
 

Eveready

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Another item to be aware of. Even if you find enough working components to get the radio to work the speakers are most likely dead or the next thing to it. When I installed a new radio I checked all 4 speakers as part of the install.

I connected a 9V battery across the terminals of each speaker in turn . NADA Nothing at all not even the expected click. The voice coil on every one of them was open. Plan on replacing the speakers as part of the process. The magnets work great on the refrigerator but the speakers themselves are crap.
 

DerekTheGreat

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Another item to be aware of. Even if you find enough working components to get the radio to work the speakers are most likely dead or the next thing to it. When I installed a new radio I checked all 4 speakers as part of the install.

I connected a 9V battery across the terminals of each speaker in turn . NADA Nothing at all not even the expected click. The voice coil on every one of them was open. Plan on replacing the speakers as part of the process. The magnets work great on the refrigerator but the speakers themselves are crap.

You just tried to quickly connect and disconnect that voltage to each speaker, right? Straight DC will fry voice coils pretty fast. Stock speakers are garb anyway, if a dude or dudette is going to be pulling those things, might as well replace with some plate speakers from Infinity... My wife drives a '92 with a stock radio and stock speakers. She refuses to listen to the radio in hers at anything louder than a normal conversation, that's how bad those speakers are and how hard on our ears they are. My truck, same deal except it has an equalizer, sports the revised, higher output brain box and Infinity plate 4x6's. It's comfortable and easy on the ears regardless of volume. I can't say enough good things about those speakers.

Thinking out loud here..... Or maybe just make sure all the existing grounds are squeaky clean????

Ken

I tried the cleaning up existing grounds thing. If the stereo is all fac-tree then you might get away with it. But when I did my auxiliary input mod, I still had the audible tachometer. Had to run the additional grounds to get rid of it as it seems GM expected the tape deck to ground out using the single ground coming out of the harness into the brain box.
 

Eveready

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You just tried to quickly connect and disconnect that voltage to each speaker, right? Straight DC will fry voice coils pretty fast.

Definitely ! I should have made that more clear, you just brush the wires from a 9v battery across the speaker terminals. You do not hook to them. A momentary contact will give you a distinct click if the speaker is functional . As @DerekTheGreat points out, prolonged contact with dc voltage could easily damage the speaker. This is a go / no go test. In many cases you will find that the stock speaker is already dead.
 

94ChevyZ71

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Wher did You send it to be refurbished?
Unitedradio.com is who I was told refurbishes them. I gave them a call a few weeks ago to get an estimate on a repair but they needed part numbers and to know what was exactly wrong. You can send them whatever you’re needing fixed and I’m sure they would fix it. I have 5 cassette players and none of them work. I’m been trying to find info on repairing them but haven’t found much. They all get power but just click when I insert a tape. I’ve cleaned them with no luck. I believe the drive belts are broke but not 100% sure.
 

AK49BWL

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99% chance the belts are broken or melted. The cassette player mechanism is held into the main body by four screws, you need to remove the front face (another four screws) to get to one of them. They're 1/4" hex screws. Once you get the cassette player free of the chassis, turn it over and carefully remove the ribbon cable for the front buttons by releasing the connector and pulling it out. Under that, there are three Philips screws holding on the bottom cover, remove those and hinge the cover off. The motor pulley and two capstan pulleys are accessible, as is the drive belt if it's still there. Don't turn the deck right-side-up with this cover off, the two large pulleys are not held in and will fall out. I can't tell you where to get replacement belts, but replacing them will probably fix your problem with them... At least mechanically.

The reason you're only hearing clicks is because these decks have little solenoids that engage gearing driven by the capstan pulleys. No belt, nothing moves.
 
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