I'm currently chasing down a flashing OD light and electrical issues. I've gone through 3 replacement radios this year on top of the flashing OD light. Something is screwy....
1) Both front speakers (in the door) ohm out open circuits. Both speakers have a good positive feed but no ground. Both speakers ohm out OK. The wires in the rubber tube in the hinge are are fine - the open circuit is between the kick panel and the radio. Wiring diagrams I have don't provide helpful information but the odds of both front speakers losing the negative connection back to the radio is suspicious.
2) Although Google search says newer car radios can operate without speakers without damage the Ford shop manuals disagree. But the rear speakers work - left and right, so I'm not sure if no front door speakers is causing a problem with the radio overheating.
3) The passenger side kick panel had a funky looking chassis ground that 6 wires used. I cleaned it up with a dremel wire wheel. All other grounds I've found look pristine.
4) The antenna cable outer shield meters out as not being grounded when I test with an ohmmeter. The Ford service manual says the outer shield should have a good ground. Radio reception is good but does the radio use the coaxial antenna cable as an additional source of ground? I removed the antenna mount and found it to be corroded. I cleaned everything up with the Dremel wire wheel and it's still testing out as open.
1) Both front speakers (in the door) ohm out open circuits. Both speakers have a good positive feed but no ground. Both speakers ohm out OK. The wires in the rubber tube in the hinge are are fine - the open circuit is between the kick panel and the radio. Wiring diagrams I have don't provide helpful information but the odds of both front speakers losing the negative connection back to the radio is suspicious.
2) Although Google search says newer car radios can operate without speakers without damage the Ford shop manuals disagree. But the rear speakers work - left and right, so I'm not sure if no front door speakers is causing a problem with the radio overheating.
3) The passenger side kick panel had a funky looking chassis ground that 6 wires used. I cleaned it up with a dremel wire wheel. All other grounds I've found look pristine.
4) The antenna cable outer shield meters out as not being grounded when I test with an ohmmeter. The Ford service manual says the outer shield should have a good ground. Radio reception is good but does the radio use the coaxial antenna cable as an additional source of ground? I removed the antenna mount and found it to be corroded. I cleaned everything up with the Dremel wire wheel and it's still testing out as open.