• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Airbag light

  • Thread starter Thread starter mustangmutt
  • Start date Start date Jul 31, 2011

mustangmutt

Member
Aug 2, 2010
339
6
18
El Paso, TX
Jul 31, 2011
#1
  • Jul 31, 2011
  • #1
Does anyone have a good source for info on airbag trouble codes. Mine appears to be flashing 33. Which is an open circuit on the passenger side airbag, 90's are not equipped with a passenger side airbag.
Thanks in advance.
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Jul 31, 2011
#2
  • Jul 31, 2011
  • #2
A 90 Air bag diagnostic monitor has single-digit error codes (not counting error code #10).
So, that means you have:
An error code of #3 - Air Bag Deployment Circuit - Low Battery Voltage or Low Backup Power Supply Voltage.

It's likely that the very old back up air bag battery has finally lost it's ability to store a charge. The newer systems use a capacitor or a "super-capacitor".

See:
Mustang 90-91 Air Bag Diagnostic Codes

Mustang 90-91 Air Bag Diagnostic Codes

http://www.veryuseful.com/mustang/tech/airBag/images/airBag89-91Code3.jpg

http://www.veryuseful.com/mustang/tech/airBag/images/airBagPartsLoc90.jpg

NOTE: BEFORE ANY AIR BAG SYSTEM REPAIR is attempted:
1) Disconnect the battery
2) Push on the brake pedal to help drain any stored charge
3) Wait 5 mins.


So, there are a few options.
1) Try to get another backup battery from an old Ford. If you can find one that still works, realize that it too will likely fail in a "few" years. But, you "might" get another 5 or 10 years from the battery.



NOTE the following options ALL VIOLATE FEDERAL LAW AND IF YOU EVER SELL THE CAR OR ANOTHER DRIVER IS IN THE CAR AND GETS INJURED IN A CRASH, YOU COULD EASILY BE SCREWED FOR ALL YOUR WORTH BY EVEN THE DUMBEST LAWYER!

AGAIN: It VIOLATES FEDERAL, and many STATE, LAWS TO MODIFY, IN ANY WAY, AN SRS (e.g. air bag) system!!


2) Simplest: As long as you don't care about having an air bag system if all of the battery power is lost before a crash (IMHO, very very unlikely),
Then: Remove the bad air bag battery back battery (see diagram for location), and connect the two wires together.


3) Get a super-cap that is rated for use in automotive systems, and replace the bad air bag battery backup with a super-cap (~$20). Splice in the wires as needed. This gives back the functionality of having an air bag in case the battery voltage is lost right before a crash. I guess if a transformer comes to life, grabs your car by the hood, takes the battery and alternator, and drops the car, then it would be good to have that functionality.


Last: Note I am NOT a lawyer, nor have any degrees or courses in law!
From what information was easily found on the interweb, and after many forum "discussions" (LOL ), it seems that Federal Law does not prohibit the owner and sole driver of the car from making mods to an SRS system. Still, if someone stole the car and got injured, the owner would be sued and mega screwed.
From what I've quickly seen, most State Laws prohibit any mods regardless of who did them and the use of the car (such as a track only car).


Good Luck!
 

Tanus

New Member
Dec 11, 2009
847
1
0
A to the Z
Jul 31, 2011
#3
  • Jul 31, 2011
  • #3
stang&2Birds said:
Remove the bad air bag battery back battery (see diagram for location), and connect the two wires together.
]
Click to expand...
good info, anybody know exactly where the battery is? In the diagram it appears to be behind the dash, on the right hand side
 

mustangmutt

Member
Aug 2, 2010
339
6
18
El Paso, TX
Jul 31, 2011
#4
  • Jul 31, 2011
  • #4
Thanks Stangs & 2 Birds (sounds like an old Indian name ), bummer, I'm fixing this car to sell it. I better fix it right. looks like I got my work gut our for me. I'll check voltage at terminals 13 & 14 and go from there.
 
S

SleepingStang

New Member
Jun 26, 2008
27
0
0
Aug 1, 2011
#5
  • Aug 1, 2011
  • #5
How about info for my 92 notch stang&2 birds fir location of battery and other info you provided?
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Aug 1, 2011
#6
  • Aug 1, 2011
  • #6
Tanus said:
good info, anybody know exactly where the battery is? In the diagram it appears to be behind the dash, on the right hand side
Click to expand...
As I understand, it's behind the glove box.
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Aug 1, 2011
#7
  • Aug 1, 2011
  • #7
mustangmutt said:
Thanks Stangs & 2 Birds (sounds like an old Indian name ), bummer, I'm fixing this car to sell it. I better fix it right. looks like I got my work gut our for me. I'll check voltage at terminals 13 & 14 and go from there.
Click to expand...
If you're selling it, then do it the easy and "right way", get another battery from the junkyard. Ford used them for a few years in a number of models. As long as you get one that lasts long enough, you're all set and legally safe and all set.

As I said, a battery from the junkyard may last 1 week, or 10 years. There are many factors and no way for knowing for sure.

Good Luck!
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Aug 1, 2011
#8
  • Aug 1, 2011
  • #8
SleepingStang said:
How about info for my 92 notch stang&2 birds fir location of battery and other info you provided?
Click to expand...
Hi.

From 92+, Ford used an internal capacitor. Also, a 92 has a two-digit fault code. A similar fault for a '92 would be "52" Backup Power Supply failure.

Mustang 1992 Air Bag Diagnostic Codes

http://www.veryuseful.com/mustang/tech/airBag/images/airBagSchem1992.jpg

A code 52 could be caused by a bad wire. But, (unless someone has screwed around with the wires), it's more likely to be caused by the internal boost/backup circuit going bad. Capacitors fail over time for a number of reasons. Other than IC ("chips"), capacitors have the highest failure rate from normal use/wear.
 
S

SleepingStang

New Member
Jun 26, 2008
27
0
0
Aug 4, 2011
#9
  • Aug 4, 2011
  • #9
Stang&2birds I am getting a code 12 flash on airbag light. Your flowchart indicates lack of battery voltage to firing circuit. This is an SSP so not sure if something is just unplugged. My horn works, so would you suspect clockspring or something else. Thanks.
 
You must log in or register to reply here.

Similar threads

D
Please help with vacuum lines
  • Dawgs000082
  • May 10, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
2
Views
86
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 10, 2026
Dawgs000082
D
K
3.8 T5 & Bellhousing to 1987 Lincoln 5.0
  • ks65stang
  • Mar 2, 2026
  • Other Auto Tech
Replies
3
Views
247
Other Auto Tech Mar 3, 2026
Noobz347
T
2002 V6 3.8L Help Me
  • TheIncompetentMechanic
  • Apr 4, 2026
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • 2 3
Replies
50
Views
679
1996 - 2004 SN95 Mustang -General/Talk- May 12, 2026
TheIncompetentMechanic
T
Trick Flow Series R to Box R Upper Intake Road Block
  • Habu135
  • Mar 31, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2 3 4
Replies
78
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 6, 2026
Habu135
2
Running very very rich
  • 2esoteric
  • Oct 31, 2025
  • Fox 5.0 Mustang Tech
Replies
4
Views
305
Fox 5.0 Mustang Tech Oct 31, 2025
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?