My airbag light is flashing a code 51 on my Ford. It sounds like it is as simple as replacing a fuse but I'm not sure where the fuse is located. Also, prior to the 51 code I was getting a 52 code, is this as simple as replacing the fuse that is part of the backup power supply circuit?

I'm not too keen on airbag repairs but I hope this link will help you get the answers you need to get you on the way to your repairs :o)
Jesus loves you, John 3:16-17 (KJV)

Airbag Code 51 flashing and a fix ( & moved here) - TCCoA Forums

If your airbag code is blinking, and you get 51, it means that your internal thermal fuse in your airbag computer is blown which is caused by an intermittant short to ground on one of the wires in the circuit. When the short to the ground is removed, code 51 flashes with the use of the airbag warning lamp, 5 flashes, pause, 1 flash, longer pause. According to the Ford, this is a nonrepairable fix, you must buy a new air bag module which is a blue box located in the vicinity of the the steering column.

code 51 comes up as
seat belt restraint or air bag clock spring

if code 51 is cleared and comes back
the sensor or clock spring has to be replaced then code cleared

The code you have indicates that the internal fuse in the airbag control module has been blown; this happens automatically when a short to ground occurs in one of the airbag circuits in the vehicle. This is a safety feature designed to prevent injuries due to accidental deployment of the airbag due to an electrical fault; the module blows the fuse intentionally to disable the system. the fuse is not serviceable; a new airbag module must be installed after the short to ground has been located and repaired. The air bag diagnostic module is located at the center of the dash panel, below the integrated control panel

I was unable to locate code 31 in my book here is a copy of the codes. looks like you just need a fuse for #51. this may fix 31 as well.

Diagnostic Trouble Code Table 1994

AIR BAG DIAGNOSTIC MONITOR DIAGNOSTIC TROUBLE CODE PRIORITY TABLE
Priority Code Component/Fault Description
Highest - No Air Bag Indicator - Inoperative Lamp Circuit or No Ignition
Voltage to Air Bag Diagnostic Monitor

Continuous Air Bag Indicator - Air Bag Diagnostic Monitor
Disconnected or Inoperative
12 Low Battery Voltage
13 Air Bag Circuit Shorted to Ground
14 Primary Crash Sensor Circuit Shorted to Ground
21 Safing Sensor Not Mounted to Vehicle Properly
22 Safing Sensor Output Shorted to Battery Voltage
23 Safing Sensor Circuit Input Feed/Return Circuit Open
24 Safing Sensor Output Feed/Return Circuit Open
32 Driver Side Air Bag Module High Resistance or Open
33 Passenger Side Air Bag Module High Resistance or Open
34 Driver Side Air Bag Module Circuit Low Resistance or Shorted
35 Passenger Side Air Bag Module Low Resistance or Shorted
42 Center Radiator Primary Crash Sensor Feed/Return Open
44 Center Cowl Primary Crash Sensor Not Mounted to Vehicle Properly
45 Center Radiator Primary Crash Sensor Not Mounted to Vehicle Properly
51 Diagnostic Monitor Internal Thermal Fuse - Fuse Blown Due to
Intermittent Short to Ground
52 Backup Power Supply - Voltage Boost Fault
53 Primary Crash Sensor Circuits - Resistance to Ground or Air Bag
Diagnostic Monitor Failure

Lowest - Rapid Continuous Flashing of Air Bag Indicator (No DTC) All Primary

Hi!

Code 51 means: Air Bag Diagnostic Monitor Internal Thermal Fuse ä Fuse Blown Due to Intermittent Short to Ground. It means that the computer controlling the airbags sensed a short in the wiring and disabled itself by tripping an internal fuse for safety reasons so that the air bag cannot be deployed accidentally. To repair the car, the wiring problem must be fixed, and then the airbag module replaced. Look for smashed wires, wires that are rubbing against bare metal or other wiring damage affecting the airbag circuits. This wiring is all under the plastic cowl around the steering column.

Please do rate the solution as FixYa and revert for further clarification.

Thanks
Rylee

Common fault on FORD

Usually due to a poor connection in the YELLOW PLASTIC CONNECTOR underneath the passenger seat.

Just push it together properly and it should clear the AirBag fault

found it.

Sounds like an air bag problem. You will not be able to reset the light without fixing the problem. The steering wheel airbag electrical contact is suspect. Airbag will have to be removed and problem repaired. . I do not recommend you repair the problem unless qualified.