B0110 – Side impact module-Left Rear high circuit is less than 2.4 volts

System: Body | Standard: ISO/SAE Controlled | Fault type: Circuit

Definition source: SAE J2012 naming/structure guidance (verify exact wording against your official DTC dataset)

B0110 – B0110 – Side impact module-Left Rear high circuit is less than 2.4 volts

B0110 means the vehicle’s body/airbag control system has detected that the left rear side impact module “high” circuit is below 2.4 volts. In real-world terms, this points to an electrical problem (not a confirmed bad module) that can cause the Supplemental Restraint System (SRS) to disable part of its side-impact protection, turn on the airbag/SRS warning light, and store a fault that must be diagnosed before the system can be trusted. Drivability usually isn’t affected, but safety is: if the circuit can’t carry the correct voltage, the system may not correctly recognize or communicate with the left rear side impact module during self-checks.

B0110 indicates the left rear side impact module high circuit is reading less than 2.4 volts, usually due to wiring/connector voltage drop, a short to ground, or a power/ground integrity problem. The main effect is an SRS/airbag warning and potentially reduced side-impact restraint functionality until repaired.

What Does B0110 Mean?

The meaning of B0110 is straightforward: the control system sees the left rear side impact module “high” circuit voltage below a 2.4 V threshold when it expects a higher value. Depending on the vehicle, the “side impact module” may be a satellite sensor/module or a node within the SRS network, but the diagnostic code definition stays focused on one fact: the monitored high circuit is too low. This is a circuit fault, so the priority is verifying power, ground, connector condition, and signal integrity at the left rear side impact module and along the harness—before condemning any module.

Theory of Operation

Under normal conditions, the SRS/Body control electronics monitor the left rear side impact module circuit(s) for expected voltage behavior during key-on self-tests and, in many designs, continuously while the vehicle is operating. A “high” circuit typically refers to a line that should sit at a known higher voltage level (for example, a supplied bias, a pull-up logic state, or a monitored feed) relative to chassis ground.

If the module, harness, or connector introduces excessive resistance (corrosion, loose terminals, damaged wires) or the circuit is unintentionally pulled toward ground (short-to-ground, moisture intrusion, chafing), the measured voltage can drop below the 2.4 V threshold. When that low-voltage condition is detected long enough to meet the enable criteria, the controller stores the B0110 diagnostic code and commands the SRS warning indicator.

Symptoms

• Airbag/SRS warning light: illuminated on the instrument cluster, sometimes with a “Service Airbag” or similar message
• Stored B0110 code: B0110 diagnostic code present in the SRS/Body system, often as current or history depending on whether the fault is intermittent
• Disabled or limited side-impact protection: the system may inhibit certain side airbag/pretensioner functions until the circuit fault is resolved
• Intermittent warning after bumps or seat movement: symptoms may come and go if the issue is a loose connector, terminal tension problem, or harness rub-through
• Additional SRS-related codes: other body/SRS circuit codes may set if the low-voltage condition affects shared power/ground, communication, or reference lines
• No drivability changes: engine performance is typically normal because B0110 is a body/SRS electrical fault, not a powertrain issue

Common Causes

• Cause: High-resistance or partially broken wiring in the Left Rear side impact module high circuit causing a voltage drop below the 2.4V threshold (common near bends, pinch points, or where the harness moves)
• Cause: Corroded, loose, water-intruded, or backed-out terminals at the Left Rear side impact module connector creating excessive resistance in the circuit
• Cause: Poor ground path (high resistance in the module ground, ground splice, or ground fastener) that drags circuit voltage down under load
• Cause: Short-to-ground on the high circuit wire (insulation rubbed through, crushed harness, contact with body metal) pulling the circuit below 2.4V
• Cause: Low supply voltage to the side impact module (power feed issue, shared fuse/relay/contact resistance) leading to reduced circuit levels and triggering B0110
• Cause: Intermittent connection/fretting at connector pins (micro-movement) producing momentary low-voltage events that set the B0110 code
• Cause: Internal fault in the Left Rear side impact module electronics that results in an abnormally low circuit voltage (confirm only after power/ground and wiring tests pass)
• Cause: Control module network/processing issue (rare) where the supervising controller interprets the circuit as low due to module communication or internal monitoring error

Diagnosis Steps

Use a capable scan tool that can read body/SRS data (not just generic OBD2), a digital multimeter with a high-impedance input, and the correct wiring diagram/pinout for your exact vehicle. Back-probing tools, terminal test adapters, and a fused jumper lead help you avoid terminal damage and reduce the risk of creating new faults while diagnosing B0110.

1. Verify B0110 is current: scan all body/SRS modules, record stored/pending codes, and save freeze-frame or failure records (voltage, ignition state, and any “intermittent” flags). Note any related side impact module or restraint system codes; address system-wide power faults first.
2. Confirm the exact circuit naming and pinouts for your vehicle: “Left Rear side impact module high circuit” can be monitored by a restraint control module or a body controller depending on design. Use the wiring diagram to identify the “high” wire, module connector pins, power feeds, and ground points.
3. Perform a careful visual inspection of the harness routing to the Left Rear side impact module: look for crushed wiring, rub-through, prior collision/repair areas, moisture paths, and evidence of seat/trim fastener intrusion. Focus on areas where the harness flexes or is clipped to sheet metal.
4. Inspect connectors and terminals: disconnect the module connector(s) only after following the manufacturer’s safety procedures for restraint-related components. Check for corrosion/green deposits, moisture, bent pins, pushed-out terminals, loose terminal tension, and damaged seals. Repair terminal fitment issues before further testing.
5. Check module power and ground integrity under load: with the circuit connected (when safe/allowed), measure voltage drop on the ground side (module ground to chassis ground) while the system is powered. Excessive ground voltage drop indicates a poor ground path that can pull the monitored circuit below 2.4V.
6. Measure the “high circuit” voltage: using back-probing (preferred) and the wiring diagram reference point, confirm whether the high circuit is actually below 2.4V when the fault is present. If the voltage is normal, attempt to recreate the failure with a wiggle test on the harness/connector while monitoring live data.
7. Check for short-to-ground on the high circuit: with power off and connectors safely disconnected as specified, measure resistance from the high circuit wire to chassis ground. A low resistance reading suggests a short-to-ground or moisture path. If resistance changes during a harness wiggle, locate the rub point.
8. Check for excessive resistance/open in the high circuit: perform end-to-end continuity testing of the high circuit wire between the monitoring module and the Left Rear side impact module connector. High resistance indicates corrosion inside the wire, damaged strands, or poor terminal crimps/splices.
9. Isolate the fault by sectioning: if continuity/short tests are inconclusive, test from intermediate connectors/splices to narrow the suspect segment. Pay special attention to splices, ground distribution points, and any connector located in moisture-prone areas.
10. Only after wiring, connector, power, and ground tests pass, suspect the module: if B0110 persists with confirmed-good circuit integrity and correct supply/ground, follow the service information to validate module function (where applicable) and determine if module replacement/programming is required.
11. Confirm the repair: clear codes, cycle ignition as specified, and road test/perform the module self-test. Re-scan to confirm B0110 does not return and that no new restraint/body codes were introduced during service.

Professional tip: Don’t replace the side impact module based on B0110 alone. In real-world diagnostics, low-voltage DTCs are more often caused by voltage drop from corrosion, poor grounds, or a partially broken wire—problems that may only show up during a wiggle test or when the circuit is loaded.

Possible Fixes

• Repair damaged wiring in the Left Rear side impact module high circuit (splice/replace the affected section, restore proper routing and abrasion protection)
• Clean, dry, and secure connectors; repair/replace corroded or loose terminals and seals to restore proper terminal tension and prevent moisture intrusion
• Restore power and ground integrity (repair ground point, splice pack, or power feed; correct excessive voltage drop)
• Repair a short-to-ground condition (find and correct harness chafing/crushing; replace compromised insulation and re-secure clips)
• Replace the Left Rear side impact module only after confirming correct power/ground and verified circuit integrity, then perform any required setup/calibration per service information
• Update/replace the supervising control module only if directed by confirmed diagnostics and service procedures (rare)

Can I Still Drive With B0110?

You can usually drive with a B0110 code because it’s a body-system circuit fault related to the left rear side impact module circuit voltage being below about 2.4 volts, not an engine or transmission performance issue. However, it may affect airbag/SRS readiness and can disable or reduce side-impact protection depending on vehicle design. Treat B0110 as a safety-related problem: drive only as needed, avoid carrying passengers if possible, and schedule diagnosis soon. If the airbag warning light is on, assume the system may not protect you as intended until the circuit fault is corrected.

How Serious Is This Code?

B0110 is typically high severity from a safety standpoint because it indicates the module (or the circuit that feeds/communicates with it) is seeing an abnormally low voltage condition on the specified circuit. That low-voltage state can be caused by wiring damage, corrosion, poor terminal tension, or a power/ground problem, any of which can interfere with correct SRS monitoring and deployment logic. Ignoring B0110 can leave the vehicle with an illuminated airbag light, stored fault history, and potentially reduced side-impact airbag operation. Diagnose it promptly, and verify the repair with a full code clear and re-check.

Repair Costs

Last updated: March 21, 2026