JPXJMOAB

Maybe somebody here can help me with one more electrical issue.. I've gotten everything else fixed but 3 separate electrical issues within a week is killing me.

My rear speakers used to cut out, until I found out if I turn the dome lights on with the headlight switch the rear speakers would come back on.. did that for a few days till I had time to start looking for the issue and now the rear speakers don't work at all. When the dome lights are turned on all I get is static and sometimes electrical sound from the engine.. in my experience that's a ground issue, but I've cleaned pretty much every ground I can find..

BlueRidgeMark

How about the radio ground? Dome light ground?

JPXJMOAB

Guess I'm just not sure as to where they ground.

BlueRidgeMark

That makes two of us!

I have never had occasion to mess with either circuit in a Cherokee, so all I can do is make an educated guess. I would expect the dome light to have a ground up there at the light itself, and the radio is almost certainly back in behind the radio somewhere. Digging required.

JPXJMOAB

The odd thing is the circuits would have to meet somewhere to have this issue.... right? Lol

nujeepguy

wiring diagram, do you have it? if not its like working with your eyes closed.
gotta get svc manual.

JPXJMOAB

I have a manual and am able to get onto all data if needed. Neither show ground locations.

BlueRidgeMark

They do.

They meet at the ground. Electrically, that's all the same place. That's why funky ground connections at individual components can affect components that seem unrelated.

From the standpoint of wandering electrons, the dome light isn't a long way from the radio, it's right next to the radio, and the rear lights, and the headlights, and.... everything else in a vehicle.

That's why bad grounds cause bizarre symptoms.

CCKen

The radio is grounded at G108, which is buried under the far left side of the dash (can't readily see it). The dome lamps are grounded at G107, which is buried under the far right side of the dash (can't readily see it). These grounds rarely go bad. Many circuits are grounded at these two points; if any one was bad other circuits would be corrupted.


With a 6 speaker system the power amplifier is grounded at G301, which is on the cabin floor. The front and sound bar speakers are driven by the power amp. In a 4 speaker system the front and rear sound bar are driven by the radio itself.


If you are chasing grounds, what's common to the above grounds is ground G100, which is the main battery to chassis ground. Radio noise suppression is by the braided strap on the firewall.


G100:



.
Radio interferance suppression bonding strap:



.

JPXJMOAB

Ok I'll have to double check those grounds. The PO replaced the ground strap with a wire

CCKen

A wire won't hack it. It needs to be a braided strap. I used the strap shown below because I cut the threaded stud end off the left read head bolt so I could torque it properly. Works fine for me. O'reilly has them.



.

JPXJMOAB

Checked the body ground by the battery, it's clean and tight.. replaced the ground strap and still rear speakers are not working .. the fronts still work perfectly. Starting to irritate me.. LOL

nujeepguy

doesnt look like it. i just have a "book" and a downloaded svc man that looks detailed. all wiring i see shows 2 wires to each speaker in all systems.
as i recall most radios for years have done that because the speakers tie direct to solid state,transistors, that dont want to be tied to ground.
its not likely the spk wires would tie to any power wires either ground or +12v.
has 'somebody" done some home made wiring in your jeep?

if the radio works, and any speaker works you have no ground problem, its wires to the speakers or mods done by someone, somewhere.
i think much is made of "ground" problems, blame, because ground seems mysterious.

JPXJMOAB

Well the speakers used to work.. I checked all the connections tonight and they look ok. I'll bring home my power probe tomorrow and check for power/ground at the speaker wires, but the wires are all original... the speakers just have a very quiet static but only with the dome lights on...

nujeepguy

once more,,,the speakers ARE NOT GROUNDED, 2 wires from radio or amp.

if the radio works on any speaker, clock, presets, you do not have a ground problem, its wires/ connectors.

or the speakers themselves possibly because they got messed up with power wiring or just miswired.

did someone mess with the wires connected to your radio?