98 Blazer radio problem

I lost sound from the 4 main speakers in a 98 blazer.  they worked 1 day, and not the next.  it has the factory HU with CD.  The dash speakers (which i believe are just tweeters) still put out sound.  i wrongly thought it was the HU and bought an Alpine 9843.  wired it up with the new harness adapter, and i still have the same problem.  the factory connection looks good.  have i lost a ground somewhere?  or is there another connection somewhere in the dash that has come loose?

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MJM

test meter the speakers... i've see a half dozen cases where all the Blazer speakers grenade at the same time....

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Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979

i have a blazer, i never heard of that. if that ever happens to me what would fix the problem? it cant be a lost ground if the dash tweeters still make sound, and yes... they are just 1" tweeters in the dash.

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99 Blazer LT.   Yellow Top. Big 3. Infinity Kappa Speakers All Around. Jensen CD/DVD flip out. 2 Infinity Kappa Perfect 12DVQs powered by a Alpine PDX600.1 (in one custom box, building a FG box)

This vehicle may have an amp under the console. Check to see if it has one and the connections that go to it from the radio.

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sparky

I never even thought of that, but come to think of it, it does get AWFUL loud for a stock system. but i dont think it has an amp. maybe the factory upgrade audio system does though? anyone know for sure?

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99 Blazer LT.   Yellow Top. Big 3. Infinity Kappa Speakers All Around. Jensen CD/DVD flip out. 2 Infinity Kappa Perfect 12DVQs powered by a Alpine PDX600.1 (in one custom box, building a FG box)

I checked and there's no external amp that has been added by the previous owner.  The left rear door speaker is working now (along with the 2 dash).  I popped open the bottom of the right rear door panel to check the wire color/connection of that speaker.  the wire colors are the same as the dash end of the factory harness, so i get a warm fuzzi that the factory harness is still used.   i haven't taken the dash apart to look for and mid-harness connectors or splices.

what should i be reading when i meter the speaker?  leave the speaker wire intact and ohm across the connection at the HU end?

why couldn't GM spend an extra 10 cents and give access to the speakers without disassembling the car?

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MJM

You should get a reading of between 4 and 10 ohms on the rear speakers. You may not get a reading on the front speakers, as the dash tweeters have a capacitor on them which won't allow your meter to read them. They are parralled in with the front door speakers. Check the very large connector above the passenger's foot well near the firewall. I think all but the dash speakers go through it.

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sparky

I still have all my factory speakers still from when i ripped them out, and yes, the backs are 9.5ohm speakers, and the fronts are 4, but with the dash tweeter yes, it may not read.

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99 Blazer LT.   Yellow Top. Big 3. Infinity Kappa Speakers All Around. Jensen CD/DVD flip out. 2 Infinity Kappa Perfect 12DVQs powered by a Alpine PDX600.1 (in one custom box, building a FG box)

I'm sorry I misunderstood you. If you replaced all your speakers then they are probably 4 ohm ones. Use a meter to check that no speaker wires are grounded.

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sparky