Air bag light fashes 46 code. I know it is the

list of airbag flash codes.

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 Circuit High Resistance or Open
33 Passenger Side Air Bag Circuit High Resistance or Open
34=Driver Side Air Bag Circuit Low Resistance or Shorted
35=Passenger Side Air Bag Circuit Low Resistance or Shorted
41=RH Primary Crash Sensor Feed/Return Circuit Open
42=LH Primary Crash Sensor Feed/Return Circuit Open
44=RH Primary Crash Sensor Not Mounted to Vehicle Properly
45=LH Primary Crash Sensor Not Mounted to Vehicle Properly
51=Air Bag Diagnostic Monitor Internal Thermal FuseFuse Blown Due to Intermittent Short to Ground
52=Backup Power SupplyVoltage Boost Fault
53=Primary Crash Sensor Circuits Resistance to Ground or Air Bag Diagnostic Fault

Ford Airbag Fault Codes
Flash Code Component/Fault Description
- No Air Bag Indicator - Inoperative Indicator Circuit
- Continuous Air Bag Indicator - Diagnostic Trouble Code Timed Out, Diagnostic Monitor
Disconnected or Inoperative, or No Ignition Voltage to Diagnostic Monitor
12 Lost Battery Feed
13 Air Bag Circuit Shorted to Ground
14 Primary Crash Sensor Circuit Shorted to Ground
21 Diagnostic Monitor Not Mounted to Vehicle Properly
22 Safing Sensor Output Circuit Shorted to Battery Voltage
23 Memory Clear Circuit Improperly Grounded
24 System Disarm Failure or Internal Diagnostic Monitor Fault
32 Driver Side Air Bag Circuit High Resistance or Open
33 Passenger Side Air Bag Circuit High Resistance or Open
34 Driver Side Air Bag Circuit Low Resistance or Shorted
35 Passenger Side Air Bag Circuit Low Resistance or Shorted
41 Right Radiator Primary Crash Sensor Feed/Return Circuit Open
42 Left Radiator Primary Crash Sensor Feed/Return Circuit Open
44 Right Radiator Crash Sensor Not Mounted to Vehicle Properly
45 Left Radiator Crash Sensor Not Mounted to Vehicle Properly
51 Airbag diagnostic Monitor Internal thermal fuse Blown
52 Back-up Power supply Voltage Boost Fault
53 Front Crash Sensor High Resistance or Diagnostic Monitor Failure

never saw a 49 code ,a weak battery or faulty battery connection
perhaps.
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 Circuit High Resistance or Open
33=Passenger Side Air Bag Circuit High Resistance or Open
34=Driver Side Air Bag Circuit Low Resistance or Shorted
35=Passenger Side Air Bag Circuit Low Resistance or Shorted
41=RH Primary Crash Sensor Feed/Return Circuit Open
42=LH Primary Crash Sensor Feed/Return Circuit Open
44=RH Primary Crash Sensor Not Mounted to Vehicle Properly
45=LH Primary Crash Sensor Not Mounted to Vehicle Properly
51=Air Bag Diagnostic Monitor Internal Thermal FuseFuse Blown Due to Intermittent Short to Ground
52=Backup Power SupplyVoltage Boost Fault
53=Primary Crash Sensor Circuits Resistance to Ground or Air Bag Diagnostic Fault

Has the vehicle been in a crash or minor accident recently? Have you installed any amps or anything under the seats? Are seatbelt tensioners working properly? These are typical issues.
Here is a list of airbag codes:
Air Bag Fault Code Table
AIR BAG DIAGNOSTIC MONITOR FAULT CODE PRIORITY TABLE
Priority Code Component/Fault Description
Highest -- No Air Bag Lamp - Inoperative Lamp Circuit or No Ignition Voltage to Diagnostic Monitor
' -- Continuous Air Bag Lamp - Diagnostic Monitor Disconnected or Inoperative
' 12 Low Battery Voltage
' 13 Air Bag Circuit or Crash Sensor Circuit - Shorted to Ground
' 21 Safing Sensor - Not Mounted on Vehicle Properly
' 22 Safing Sensor Output Circuit - Shorted to Battery Voltage
' 23 Safing Sensor Input Feed/Return Circuit Open
' 24 Open in Circuit 944B or Low Resistance in Crash Sensor(s)
' 32 Driver Side Air Bag/Safing Sensor Circuit - High Resistance or Open
' 33 Pin 7 Not Grounded at Diagnostic Monitor
' 34 Driver Side Air Bag/Safing Sensor Circuit - Low Resistance or Shorted
' 35 Low Resistance Across Pins 8 and 9 at Diagnostic Monitor
' 41 Crash Sensor Circuit - High Resistance or Open
' 44 RH Crash Sensor - Not Mounted to Vehicle Properly
' 45 Center Radiator Crash Sensor - Not Mounted to Vehicle Properly
' 46 LH Crash Sensor - Not Mounted to Vehicle Properly
' 51 Diagnostic Monitor Internal Thermal Fuse - Blown and Short to Ground No Longer Exists
' 52 Backup Power Supply - Voltage Boost Fault
' 53 Internal Diagnostic Monitor Fault
Lowest -- Rapid Continuous Flashing of Air Bag Lamp - All Crash Sensors Disconnected

This is a code 46 LH Crash Sensor - Not Mounted to Vehicle Properly. Often there is a poor contact on one of the wiring connectors. Some of the problems can happen from a poor connection where everything connects under the drivers side seat.
Here is a list of codes for the airbag light issues.

Air Bag Fault Code Table

AIR BAG DIAGNOSTIC MONITOR FAULT CODE PRIORITY TABLE

Priority Code Component/Fault Description

Highest -- No Air Bag Lamp - Inoperative Lamp Circuit or No Ignition Voltage to Diagnostic Monitor

' -- Continuous Air Bag Lamp - Diagnostic Monitor Disconnected or Inoperative

' 12 Low Battery Voltage

' 13 Air Bag Circuit or Crash Sensor Circuit - Shorted to Ground

' 21 Safing Sensor - Not Mounted on Vehicle Properly

' 22 Safing Sensor Output Circuit - Shorted to Battery Voltage

' 23 Safing Sensor Input Feed/Return Circuit Open

' 24 Open in Circuit 944B or Low Resistance in Crash Sensor(s)

' 32 Driver Side Air Bag/Safing Sensor Circuit - High Resistance or Open

' 33 Pin 7 Not Grounded at Diagnostic Monitor

' 34 Driver Side Air Bag/Safing Sensor Circuit - Low Resistance or Shorted

' 35 Low Resistance Across Pins 8 and 9 at Diagnostic Monitor

' 41 Crash Sensor Circuit - High Resistance or Open

' 44 RH Crash Sensor - Not Mounted to Vehicle Properly

' 45 Center Radiator Crash Sensor - Not Mounted to Vehicle Properly

' 46 LH Crash Sensor - Not Mounted to Vehicle Properly

' 51 Diagnostic Monitor Internal Thermal Fuse - Blown and Short to Ground No Longer Exists

' 52 Backup Power Supply - Voltage Boost Fault

' 53 Internal Diagnostic Monitor Fault

Lowest -- Rapid Continuous Flashing of Air Bag Lamp - All Crash Sensors Disconnected

Hope this helps...

Get the fault code.

DTCa LFCb LFC Priority Description B1318 - - Ignition Voltage Below 9 Volts - - 1 RCM Disconnected, Inoperative, or Lost/Low Ignition Feed B1342 24 2 RCM is Faulted B1231 19 3 RCM Crash Data Memory Full B1921 21 4 RCM Bracket Ground Resistance High C1414 29 5 Incorrect Vehicle Identification Code B1887 15 6 Driver Air Bag Circuit Shorted to Ground B1916 15 7 Driver Air Bag Circuit Shorted to Battery or Ignition B1888 16 8 Passenger Air Bag Circuit Shorted to Ground B1925 16 9 Passenger Air Bag Circuit Shorted to Battery or Ignition B1932 32 10 Driver Air Bag Circuit Resistance High B1933 33 11 Passenger Air Bag Circuit Resistance High B1934 34 12 Driver Air Bag Circuit Resistance Low B1935 35 13 Passenger Air Bag Circuit Resistance Low B1901 14 14 Front External Crash Sensor Shorted to Ground B1941 41 15 Front External Crash Sensor Open Circuit or Short to Battery B2444 48 16 Driver Side Crash Sensor Internal Fault B2445 49 17 Passenger Side Crash Sensor Internal Fault B2441 42 18 Driver Side Crash Sensor Mounting Fault B2440 43 19 Passenger Side Crash Sensor Mounting Fault U2017 44 20 Driver Side Crash Sensor Communication Fault U2018 45 21 Passenger Side Crash Sensor Communication Fault B1993 36 22 Driver Side Air Bag Circuit Shorted to Ground B1992 36 24 Driver Side Air Bag Circuit Shorted to Battery or Ignition B1994 36 26 Driver Side Air Bag Circuit Resistance High B1995 36 28 Driver Side Air Bag Circuit Resistance Low B1997 37 23 Passenger Side Air Bag Circuit Shorted to Ground B1996 37 25 Passenger Side Air Bag Circuit Shorted to Battery or Ignition B1998 37 27 Passenger Side Air Bag Circuit Resistance High B1999 37 29 Passenger Side Air Bag Circuit Resistance Low B1892 - 30 Air Bag Tone Warning Indicator Circuit Shorted to Ground or Open B1891 - 31 Air Bag Tone Warning Indicator Circuit Shorted to Battery or Ignition B1869 Tonec 32 Air Bag Indicator Inoperative B1870 Tonec 33 Air Bag Indicator Shorted to Battery - - - No Communication With the Restraints Control Module (RCM)
a DTC: Diagnostic trouble code
b LFC: Lamp fault code, flashed on air bag indicator.

Pinpoint Test R: Diagnostic Trouble Code 44 — RH Radiator Primary Crash Front Air Bag Sensor Not Mounted to Vehicle Properly Normal Operation
NOTE: Circuit 618 (BL/W) is grounded to the side of the RH radiator primary crash front air bag sensor case, and the case is grounded through the bracket to the vehicle at its mounting point.
The air bag diagnostic monitor (14B056) measures the resistance between pin 20 (circuit 618 [BL/W]) and pin 3 (circuit 57M [BK]), the air bag diagnostic monitor reference ground. If the air bag diagnostic monitor measures a difference of more than 2.0 ohms between pin 20 and pin 3, it will flash diagnostic trouble code (DTC) 44.
Possible Causes
High resistance on pin 20 (circuit 618 [BL/W]) to ground can be caused by:

• A poor connection due to loose mounting, dirt, or corrosion at the RH radiator primary crash front air bag sensor bracket mounting location.
• An open or damaged wire in circuit 618 (BL/W) from pin 20 of the air bag diagnostic monitor connector to the RH radiator primary crash front air bag sensor connector.
• An open circuit inside the RH radiator primary crash front air bag sensor.

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

Seems to be a very common problem with Ford. The wiring harness beneath the drivers seat contains the sensors for the airbag system. Go under the drivers seat and secure all the wires and clips. This makes most error lights for the airbags go away. Hope this helps and good luck!

 12 Low Battery Voltage 
| 13 Air Bag Circuit or Crash Sensor Circuit - Shorted to Ground 
| 21 Safing Sensor - Not Mounted on Vehicle Properly 
| 22 Safing Sensor Output Circuit - Shorted to Battery Voltage 
| 23 Safing Sensor Input Feed/Return Circuit Open 
| 24 Open in Circuit 944B or Low Resistance in Crash Sensor(s) 
| 32 Driver Side Air Bag/Safing Sensor Circuit - High Resistance or Open 
| 33 Pin 7 Not Grounded at Diagnostic Monitor 
| 34 Driver Side Air Bag/Safing Sensor Circuit - Low Resistance or Shorted 
| 35 Low Resistance Across Pins 8 and 9 at Diagnostic Monitor 
| 41 Crash Sensor Circuit - High Resistance or Open 
| 44 RH Crash Sensor - Not Mounted to Vehicle Properly 
| 45 Center Radiator Crash Sensor - Not Mounted to Vehicle Properly 
| 46 LH Crash Sensor - Not Mounted to Vehicle Properly 
| 51 Diagnostic Monitor Internal Thermal Fuse - Blown and Short to Ground No Longer Exists 
| 52 Backup Power Supply - Voltage Boost Fault 
| 53 Internal Diagnostic Monitor Fault 
Lowest -- Rapid Continuous Flashing of Air Bag Lamp - All Crash Sensors Disconnected