How serious are you about digging into the IC-7000?
Are you comfortable working on little bitty SMD devices and taking the radio apart?
I ask because working all through the drawings and troubleshooting does take a bit of effort.
The schematics are posted here I believe and tracking down the suggestion on the pull up resistor is a good start.?
However if the tracking is not going to be productive...
You could check the voltage on the PTT line on the accessory plug. If it is not high there then it can't be high deeper in the radio.
The same would apply to the mike PTT on the front and back.?
Data socket pin 3, Acc socket pin 3 HSEND pin 7 VSEND.
Pin 9 on the acc is the key line to the AT-180.
I think pin 6 on the mike jack.
The most likely points of failure are where the radio communicated with the outside world.
