Air Bag Scan Codes

bigbipper · July 3, 2014

Hello All,

The battery died a few weeks back in my 2005 Suburban. I jumped the battery and then it threw a "Service Airbag" message and light. I scanned the codes and I got BOTH a B0100 and a B0103.

I see that they are for both front sensors. I mean...what are the chances that BOTH just went bad?

Any suggestions for I replace both?

Thanks so much, guys...and gals.

txab · July 3, 2014

Clear them and see if they return. Also make sure your electrical system is in shape, i.e. battery, alternator, cables, grounds

Doug_Scott · July 3, 2014

Without even knowing what the codes mean, my best guess is they have something like low voltage in the meaning. When the battery failed, it supplied a low voltage. As suggested above, replace battery, have starting/charging system checked, reset the codes, or have a shop do it, and drive. If codes come back, then look into it.

gmtech4 · July 4, 2014

^^^^^^^^^^^ yup !!!

bigbipper · July 4, 2014

Clear them and see if they return. Also make sure your electrical system is in shape, i.e. battery, alternator, cables, grounds

Thanks much.

I did clear them and BOOM...came right back.

Battery and alternators are strong. Have read a lot about "Unplugging" the sensors, then plugging them back in. Sounds like that could work on 1 sensor, but the dual codes really make make think something else may be happening.

bigbipper · July 4, 2014

Without even knowing what the codes mean, my best guess is they have something like low voltage in the meaning. When the battery failed, it supplied a low voltage. As suggested above, replace battery, have starting/charging system checked, reset the codes, or have a shop do it, and drive. If codes come back, then look into it.

Actually, correction on the battery. I did mentioned that it was drained from playing the radio too long. However, the battery was brand new prior to this bonehead mistake; maybe 2 months old.

Wouldn't it charge itself back up to proper specs?

txab · July 4, 2014

I'd still check electrical thoroughly. These trucks are pretty picky about power supplies and wiring. Disconnecting and reconnecting the sensors can't hurt

gmtech4 · July 4, 2014

It's a hard code, it has to be gone thru by a technician not a truck owner

Doug_Scott · July 4, 2014

Actually, correction on the battery. I did mentioned that it was drained from playing the radio too long. However, the battery was brand new prior to this bonehead mistake; maybe 2 months old.

Wouldn't it charge itself back up to proper specs?

\Not sure where you mentioned the part about the radio, it was not in this thread. Same for the part about resetting the codes, and they came right back. When I post a question on multiple sites, I compose the post in notepad, then paste it on each site. That way all forums get the exact same post, and I don't forget to include something on one forum.

If the charging system is working correctly it may be able to bring the battery back. I say "may" because not all batteries will come back from being run flat. But that is why new ones come with warranties. Worst thing you can ever do when diagnosing something is to assume it must be working, its new. If that was the case 100% of the time, the part would not require a warranty of any kind.

Follow the wires back from the sensors and unplug, inspect, clean and reconnect all connectors in those circuits. That is about the limit for the backyard mechanic on troubleshooting air bag circuits. Personally I would not take anyone's advice beyond this point on servicing the air bag circuit, and I am a licenced mechanic who started down this road in 1977. Come to think of it, I just recalled reading a popular mechanics magazine article that talked about this way in the future safety thing call an air bag.

gmtech4 · July 5, 2014

\Not sure where you mentioned the part about the radio, it was not in this thread. Same for the part about resetting the codes, and they came right back. When I post a question on multiple sites, I compose the post in notepad, then paste it on each site. That way all forums get the exact same post, and I don't forget to include something on one forum.

If the charging system is working correctly it may be able to bring the battery back. I say "may" because not all batteries will come back from being run flat. But that is why new ones come with warranties. Worst thing you can ever do when diagnosing something is to assume it must be working, its new. If that was the case 100% of the time, the part would not require a warranty of any kind.

Follow the wires back from the sensors and unplug, inspect, clean and reconnect all connectors in those circuits. That is about the limit for the backyard mechanic on troubleshooting air bag circuits. Personally I would not take anyone's advice beyond this point on servicing the air bag circuit, and I am a licenced mechanic who started down this road in 1977. Come to think of it, I just recalled reading a popular mechanics magazine article that talked about this way in the future safety thing call an air bag.

1979 here doug ya old fart lol !!!

bigbipper · July 9, 2014

Ok, so I noticed that this is where my Battery reading is currently living while the truck is running. Concerns?

txab · July 9, 2014

Doesn't look like your "battery and alternator are strong". Get them checked out, along with cables and grounds

Doug_Scott · July 9, 2014

Try using a quality volt meter directly on the battery, and also check output at the big wire on alternator. Factory gauges are not 100% correct. Some are closer than others. Sort of like the fuel gauge, and temp gauge. Most gauges depend upon good supply to the gauge and good ground on way out.

When you start the engine cold, how long before gauge hits the final voltage?

bigbipper · July 12, 2014

Thanks for your input, guys. I pulled the plugs on both sensors, reconnected, cleared codes...but they promply returned. I am not convinced that both sensors are bad. The focus has now fully shifted on the electrical and charging system.

bigbipper · November 3, 2014

Try using a quality volt meter directly on the battery, and also check output at the big wire on alternator. Factory gauges are not 100% correct. Some are closer than others. Sort of like the fuel gauge, and temp gauge. Most gauges depend upon good supply to the gauge and good ground on way out.

When you start the engine cold, how long before gauge hits the final voltage?

This truck has not got much work since I last posted here, but here comes winter and an over due inspection. Airbag warning light remains on with a b0100 and b0103

A voltometer has shown the following readings:

Battery (ignition off): 12.9v

Battery (ignition on): 14.4

Alternator (igintion on, red lug and grounded): 14.8

I have to assume that means the charging system is in proper order?

The following troubleshooting has been completed:

Clear codes (only to come back)
Remove Negative cable for an hour
Unplugged/Plugged air bag fuse
Unplugged/Plugged both front sensors

The one thing I am yet to try is a new battery, but as mentioned, this was a brand new batter that I drained accidentally and had to jump. After the jump is when the Airbag light and codes were thrown.

I'm guessing my next stop is to my mechanic.

Thanks to all who chimed in. Appreciate your time and efforts.