B0013 Driver steering wheel air bag, stage 2 firing circuit fault

Driver air bag deployment loop stage 2 / Service Air Bag light

B0013 in short

On Chevrolet vehicles, B0013 means the air bag computer found a fault in the stage 2 firing circuit of the driver steering wheel air bag. Chafed coil wires, a damaged shorting bar or a loose connector are the usual findings. The driver air bag may not work, so have it checked soon and never probe air bag wiring yourself.

The driver air bag has two firing stages, and the computer (the sensing and diagnostic module) watches each circuit for an open, a short or a resistance outside its normal window. B0013 is the second stage. A companion code, B0012, is the first stage, and the two often appear together.

The circuit runs from the module through the wiring and the steering wheel coil to the air bag. GM service information has the technician confirm the loop resistance stays in range while the steering wheel is turned from lock to lock, which points at the coil, its wires and its connectors.

Many GM bulletins tie B0012 and B0013 to small physical faults rather than a failed air bag: wires chafed on the horn plate, a damaged shorting bar inside the steering wheel module, a short in the yellow air bag harness, or a connector retainer that is loose or missing. The code is not defined the same way on every make, so this page covers only Chevrolet.

Pick your make

B0013 is a manufacturer-specific code: its meaning depends on who built the car.

Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.

Most likely causes

  1. Steering wheel air bag wiring chafed, shorted or damaged shorting bar

    Supported by vehicle data
    Why it ranks here
    GM summaries describe chafed coil wires grounding on the horn plate (2008-2009 Cobalt, HHR, G5, Solstice, Sky), a damaged shorting bar with symptom byte 0E (2012 Cruze, Verano) and a short to ground in the yellow harness (2006-2009 Cobalt, HHR, Solstice, G6, Sky). The bulletins are unverified summaries.
    What would change this
    Rises with symptom byte 02 or 0E (short to ground or low resistance) on a model GM names. Falls if the fault is an open (04) or the wiring and shorting bar are intact.

  2. Air bag connector loose, or its position assurance retainer missing or broken

    Supported by vehicle data
    Why it ranks here
    GM's bulletin 08-09-41-002H, and its earlier revisions, covers intermittent air bag lights with B0012 and B0013 among the listed codes and prescribes reseating the connector and checking or replacing the CPA retainer.
    What would change this
    Rises if the light comes and goes and a dealer finds a loose connector or poor terminal fit. Falls if the connector is fully seated and its retainer is intact.

  3. Worn or open steering wheel coil (clockspring)

    Possible — needs testing
    Why it ranks here
    The loop passes through the steering wheel coil and GM's test holds the loop in range through full steering wheel rotation. One 2018 Silverado owner reports the warning and a dead horn together, which fits a coil fault, but one report is thin evidence.
    What would change this
    Rises if the fault changes with steering wheel position or the horn and steering wheel switches also fail. Falls if the loop reads steady through full rotation.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Have the air bag codes read with a scan tool that shows the symptom byte after B0013, and note every stored code, especially B0012.

    Low riskTool: scan tool with airbag (SRS) access

    • IfSymptom byte 02 or 0E (short to ground or low resistance), or B0012 stored with it

      It meansGM bulletins tie this pattern to chafed wires or a damaged shorting bar.

      Go to step 2

    • IfSymptom byte 04 or 0D (open or high resistance)

      It meansThe circuit is not complete; connector fit and the steering wheel coil come first.

      Go to step 2

    • IfThe light has come on after a collision

      It meansThe system may have fired parts that need replacing; do not rely on the air bags.

      Go to step 3

  2. Ask a Chevrolet dealer whether your VIN falls under a campaign or bulletin for B0012 and B0013, such as the 2009 Cobalt and 2008-2009 HHR special coverage.

    Low risk

  3. Have a dealer or trained technician run the air bag circuit diagnosis from the service manual, including loop resistance through full steering wheel rotation.

    Best left to a shopTool: maker's diagnostic tool and multimeter

    Warning:Airbags and seat belt pretensioners can still fire for about three minutes after the battery is disconnected, and test lights or meters on airbag circuits can set them off. Never unplug, probe or test airbag wiring yourself; leave this to a dealer or trained technician.

Symptoms

  • Air bag (SIR) light on, or a "Service Air Bag" or "Safety Restraint System" message
  • Air bag light that comes on and goes off
  • Horn or steering wheel switches stop working along with the air bag light
  • Air bag light on after a collision Gets more serious: stop and have it checked.

How to fix

This is a safety-critical system, so we explain the code but don't give repair steps. Have it inspected by a qualified technician.

Parts and cost context

  • Steering wheel air bag wiring, coil and connector:Dealer or trained-technician work only. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Chevrolet

  • 2007–2009 · Cobalt

    Supported by vehicle data

    GM bulletins name the steering wheel coil wires chafing on the horn plate (2009) and a short to ground in the yellow harness (2007-2009). Whether either is still current is not verified.

  • 2008–2009 · HHR

    Supported by vehicle data

    Same two GM bulletins as the Cobalt: horn plate chafing on 2008-2009 and a yellow harness short on 2008-2009. Whether either is still current is not verified.

  • 2012 · Cruze

    Supported by vehicle data

    GM's summary names a damaged shorting bar in the steering wheel module when B0012 or B0013 sets with symptom byte 0E. Whether it is still current is not verified.

  • 2010–2011 · Malibu

    Supported by vehicle data

    GM engineering was still collecting vehicles to find the root cause of B0012 or B0013 with the SIR light on. Whether that ever led to a repair is not verified.

  • 2018 · Silverado 1500

    Possible — needs testing

    One 2018 owner reports a shop reading B0013 with a Safety Restraint System warning and a horn that stopped working, which would fit a steering wheel coil fault. A single report, not a confirmed pattern.

  • PIC5702 (chevrolet)Status unverified

    Air bag light with B0012 or B0013 and symptom byte 0E

    2012cruze · NHTSA 10045339

    May be a damaged shorting bar in the steering wheel air bag module.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 14314 (chevrolet)Status unverified

    Special coverage: steering wheel air bag coil wires chafing on the horn plate

    2008–2009cobalt, hhr · NHTSA 10134766

    Coil wires to the driver air bag may chafe on the horn plate and set B0012 or B0013; the dealer tapes the two yellow SIR wires and the plate and replaces the coil if the wires are damaged.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • SB-09-09-41-004 (chevrolet)Status unverified

    Air bag indicator on with B0012 or B0013: install protective material

    2007–2009cobalt, hhr · NHTSA 10032335

    May be a short to ground in the yellow SIR wiring harness; the bulletin has protective material installed.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • PIE-0118Status unverified

    Engineering information: SIR light on with B0012 or B0013

    2010–2011malibu · NHTSA 10036264

    Engineering was still looking for the root cause and asking to gather vehicles before repair.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 08-09-41-002HStatus unverified

    Intermittent air bag light: inspect and replace connector position assurance retainer

    2006–2014malibu, impala · NHTSA 10137623

    Terminal replacement or connector reseating, plus inspecting or replacing the CPA retainer at the air bag for the set code.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Cadillac

  • 2015 · CTS

    Supported by vehicle data

    GM issued a bulletin for the air bag light with B0012 or B0013 on the 2015 ATS and CTS, but the summary does not give the repair. Whether it is current is not verified.

  • 2015 · ATS

    Supported by vehicle data

    Same GM bulletin as the 2015 CTS; the summary does not give the repair.

  • 2006–2008 · DTS

    Supported by vehicle data

    Same GM bulletin as the Lucerne; the summary does not give the repair.

  • PI1474Status unverified

    Air bag indicator on with B0012 or B0013

    2015ats, cts · NHTSA 10113629

    Covers a customer concern of the air bag light with B0012 or B0013 set; the summary does not state the repair.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • PIC-4871A (cadillac)Status unverified

    Service Air Bag message with SIR light and B0012, B0013, B0019, B0020

    2006–2008dts · NHTSA 10026687

    Covers a Service Air Bag message with those codes set; the summary does not state the repair.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Buick

  • 2006–2008 · Lucerne

    Supported by vehicle data

    GM bulletin PIC-4871A covers a Service Air Bag message with B0012 and B0013 among the codes; the summary does not give the repair. Whether it is current is not verified.

  • PIC5702 (buick)Status unverified

    Air bag light with B0012 or B0013 and symptom byte 0E

    2012verano · NHTSA 10045339

    May be a damaged shorting bar in the steering wheel air bag module.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • PIC-4871A (buick)Status unverified

    Service Air Bag message with SIR light and B0012, B0013, B0019, B0020

    2006–2008lucerne · NHTSA 10026687

    Covers a Service Air Bag message with those codes set; the summary does not state the repair.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • B0012Fault in the passenger-side front airbag firing circuit (resistance low)

    Shares causes Supported by vehicle data

    B0012 is the first stage and B0013 the second stage of the same driver steering wheel air bag loop; GM bulletins list them together and give the same causes.

All Airbags and seat-belt restraints (SRS) codes

B0013 questions

Does B0013 mean the same thing on every car?

No. The generic SAE table lists B0013 as a passenger knee bolster fault, while GM service information and Chevrolet owners describe it as the driver steering wheel air bag, stage 2 circuit. This page covers Chevrolet only.

Can I drive with B0013 set?

The car will drive, but the driver air bag may not deploy in a crash, so book a check soon. Do not test or unplug air bag connectors yourself.

Sources and review

  1. DTC B0012 or B0013, Saab 9-4x 2011 airbag (SRS) fault diagnosis — General Motors / Saab Automobile
  2. GM bulletin 14314 (NHTSA 10134766) — General Motors (NHTSA manufacturer communication)
  3. Nissan Supplemental Restraint Systems: damage analysis and repair using diagnostic trouble codes (Nissan TechNews, Summer 2016) — Nissan North America
  4. GM bulletin PIC5702 (NHTSA 10045339) — General Motors (NHTSA manufacturer communication)
  5. GM bulletin SB-09-09-41-004 (NHTSA 10032335) — General Motors (NHTSA manufacturer communication)
  6. GM bulletin 08-09-41-002H (NHTSA 10137623) — General Motors (NHTSA manufacturer communication)
  7. NHTSA complaint 11474524 (2018 Chevrolet Silverado 1500) — NHTSA Office of Defects Investigation (consumer complaint)
  8. GM bulletin PIE-0118 (NHTSA 10036264) — General Motors (NHTSA manufacturer communication)
  9. GM bulletin PI1474 (NHTSA 10113629) — General Motors (NHTSA manufacturer communication)
  10. GM bulletin PIC-4871A (NHTSA 10026687) — General Motors (NHTSA manufacturer communication)
  11. B0013 trouble code definition — troublecodes.net
Last reviewed
Written by
Saurabh K.
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