B14B0

Code

Generic B — Body

Airbag Control Module Internal Fault

Brand: Generic

Type: B — Body

Views: UK: 15 EN: 18 RU: 16

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Internal module hardware failure (CPU, memory, capacitors, solder joints)
Corrupted or failed module software/firmware
Low or intermittent supply voltage to the SRS module (battery or ignition feed)
Poor ground connection or corroded module connector pins
Water intrusion, corrosion, or physical damage to the module
Shorts or opens in the airbag wiring harness

Symptoms

SRS / airbag warning lamp illuminated on dash
Possible inability to communicate with the airbag control module via diagnostic tool
Diagnostic trouble codes related to module internal faults and possible lost communications
Airbags/pretensioners may be disabled or inhibited until fault is cleared and verified
Occasional or permanent loss of stored crash data or inconsistent crash-data retrieval

What to check

Read and record all SRS/airbag and network codes and freeze-frame data with a capable scan tool
Check battery voltage and charging system; repair low-voltage conditions before testing SRS
Visually inspect airbag control module and connector for corrosion, water damage, bent pins, or impact marks
Inspect wiring harness for chafing, shorts, broken wires, or repairs near the module and seatbelt pretensioners
Check module ground(s) and chassis bonding for tightness and corrosion
Verify ignition-switched and constant power present at the module using a multimeter

Signal parameters

Battery/constant power (B+) at module: ~12–14.5 V (engine running or charging as appropriate)
Ignition-switched supply (IG) at module: present only with key on/start (~12 V when on)
Module ground: near 0 V with good continuity to chassis ground
CAN bus idle voltages (if applicable): CAN_H ≈ 2.5–3.5 V, CAN_L ≈ 1.5–2.5 V (approx. 2.5 V midpoint)
Wake/standby current: should be within manufacturer specification (excessive current may indicate fault)
Module response to diagnostic request: expected diagnostic ACK/response within tool timeout

Diagnostic algorithm

Safety first: follow manufacturer SRS safety procedure. Disable battery negative and wait specified time before disconnecting SRS wiring.
Use a capable scan tool to read all SRS and network codes; save freeze-frame and code history.
Verify battery voltage and charging system. Recharge or maintain battery at service voltage before testing.
Visually inspect the SRS control module and connector. Look for corrosion, moisture, bent pins, or evidence of impact.
With the battery connected and ignition ON, measure module supply and ground voltages at the module connector. Compare to expected values.
Check CAN/SRS bus communication with a scan tool or oscilloscope. Look for valid bus activity and correct idle voltages.
Wiggle-test harness and connectors while monitoring DTCs and module communication to detect intermittent faults.
If wiring and supplies are good but the internal fault persists, check for available software updates or service bulletins and attempt a re-flash or module reprogram per manufacturer procedure.
If reprogramming is unsuccessful and all external causes have been ruled out, consider module replacement. Ensure replacement unit is the correct part and must be programmed/configured and initialized per manufacturer instructions.
After repair or replacement, clear codes, perform required SRS system initialization/calibration, and verify the SRS lamp goes out and no related codes return. Re-test system operation.

Likely causes

Failed internal memory (EEPROM) or processor fault inside the airbag control module
Loss or dropout on the 12 V supply or ignition-switched supply to the module
Corroded/damaged connector or pin causing intermittent internal fault
Module experienced water ingress or physical shock causing internal component failure
Software corruption requiring reflash or updated calibration

Fault status

⚠️ Status

Airbag control module internal fault detected. Module may be non-functional, unable to communicate reliably, or storing invalid data. SRS warning lamp is likely ON and airbag deployment may be disabled until the fault is addressed.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1.0-3.0 hours