Car Audio YODA's: Need Info

My 2000 XJ's drivers side speaker quit working. So, I took it to a local car audio installer to have them run a new wire thru the door to bypass the door hinge. Later, I noticed that the left front speaker didn't seem as loud as the passenger side when balancing it left to right. I bought some new speakers at Wally World and they did the same.

I pulled the stock head unit and discovered that they ran the positive wire from the new speaker to the LEFT (drivers side) speaker (dark green) and the negative wire to the negative wire of the (passenger) side speaker (dark blue/red).

I figured they would have ran it to the dark green (+) and brown/red (-) that is supposed to supply the drivers side speaker. Why would they do this? A friend thinks they may have discovered my stock head unit had a "blown channel" or they blowed it and then "rigged" it to work.

97-2001 Wiring:

Left Front (+) Dark Green
Left Front (-) Brown/Red
Right Front (+) Purple
Right Front (-) Dark Blue/Red
Any input?

Thanks

Try connecting it the way it's supposed to be and if that channel is indeed blown, get a new head unit.

gradon said:

Try connecting it the way it's supposed to be and if that channel is indeed blown, get a new head unit.

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That's sort of my plan. But with the "floating" ground that jeep use, I just wanted some expert input on why this may be happening. I'd hate to buy another head and "blow" it also. Also, I am unsure if this is indeed a symptom of a blown channel. Never had a similar problem.

Where did they splice the new wire? It's common for the wire to break in or near the rubber bellows between the door and jamb, especially the driver's door, the most used. I'm guessing there's a connector just inside, under the dash, although we have older models so I don't know for sure. I think all the grounds should be common, so using the wrong ground shouldn't matter. Possibly, if the channel is blown, the broken wires shorted? Does your Jeep have the amp under the back seat? If so, splicing into the head-unit's output would result in lower sound output. Possibly disconnect the wires at the radio, and check them with a meter. See if they offer 4-8 ohms resistance. Make sure there's no shorts in the system.

The stock unit has the same speaker return for the front/rear on each channel, but I don't recall offhand if it's also common left/right. I'll have to see if I still have the bits from my old gutted stock unit around later tonight so I can trace the PCB a little.

On pre-97, there is in fact the connector under the kick panel that heyhar refers to, I'm not sure about 97+ but I would assume so, since that's where the door harnesses link into the cross-body harness.

kastein said:

The stock unit has the same speaker return for the front/rear on each channel, but I don't recall offhand if it's also common left/right.

Click to expand...

Would this keep the left speaker from working as long as the wiring was OEM? When I hook the stock head unit up as it's supposed to be, the left speaker will not work. If it's wired as the stereo shop had it it will work, but with diminished output. Can the stock unit have (or be capable of having) a "blown" channel? If so, would it cause my symptoms. I was gonna try an get a cheap unit from a junk yard to diagnose the problem. I do not have an amplifier, just a stock system.

Thanks

Yes, the stock unit can break - if you want to test this you can temporarily swap the wires for the left front and any of the other speakers right at the head unit plug. If the left speaker suddenly works and the one you swapped it with doesn't, it's the head unit. If the left speaker continues to not work, it's the wiring or the speaker itself.

It's fixed! Today, I took the new wire they had spliced in behind the head unit and spliced into the wiring at the kick panel. It now works as it should.

I would have thought a "car audio" business would have been able to properly fix my problem instead of doing a rig job. I will be stopping by Monday to demand my money back.

Thanks to all.

Most of those shops hire completely uneducated idiots to do the wiring. I've fixed that kind of mess on many friend's vehicles.