I would not try and repair yourself unless you have some very good soldering equipment, and good de-soldering equipment. FEMs are hard to find and
if you damage them in any way the few repair facilities there are will not touch them.

I used to work on Motorola hand held radios and have the soldering equipment to work on them, and even with that I decided not to touch the FEM, I
sent it off for repair which was a wise decision.

Some of the transistors are very hard to find, which is usually what is wrong, and many of the ICs are 40 leg ICs, and very difficult to unsolder the IC
legs, they are very close together.
I have the equipment and thought I'd at least try to trace the problem. I've heard that a bad transistor has been found to be the issue sometimes.
Hello. Hoping someone would be able to pass along some information that could help me locate and identify FEM/REM wires that run from relay board. I was told to check whether or not these have gotten loose/check their voltage before sending out my FEM/REM for repair. Any advice or links to wiring diagrams for my make/model would be greatly appreciated. Thank you!
What relay board are you referring to, and what seems to be the problem that you think you need to send the FEM or REM out for repairs?

1955 Thunderbird Blue
Replace the FME module and the battery. All – warning lights flash on and off gauges flash, operating in a non-operating like every 10 seconds. What should I look for? How do I correct it?
Since you had the FEM disconnected, are all of the FEM connectors fully seated in the FEM? If so, start by checking the fuses to make sure that when you replaced the FEM that it didn't cause an open circuit across one of the fuses. Remember, there are 3 fuse boxes in the car, one near the battery by the spare tire, one under the right kick panel inside the car and one under the hood. Next, using a scan tool, not just an OBD code reader, check for faults stored in all control modules. Fault codes might help you determine the cause of your warning lights and gauge concerns. Note any DTCs and freeze frame data that are stored before clearing the fault codes. After clearing the fault codes do the warning lights and gauges operate normally? After clearing the fault codes do any fault codes return?

1955 Thunderbird Blue