Mitsubishi-specific code — factory diagnostic data| DTC Data Sheet | |
| System | Body |
| Standard | Manufacturer Specific |
| Fault type | General |
| Official meaning | Passenger pretensioner squib open |
Definition source: Mitsubishi factory description · Autel MaxiSys Ultra & EV. Diagnostic guidance is based on factory-defined fault logic for this code.
B1C49 means the airbag system found a problem with the passenger seat belt pretensioner circuit. In plain terms, your 2016 Mitsubishi Outlander may not tighten the passenger belt in a crash, and the SRS warning lamp will stay on. According to Mitsubishi factory diagnostic data, this code indicates a “Passenger pretensioner squib open.” That “open” wording matters. The SRS ECU does not “see” the correct electrical load in the pretensioner igniter circuit. Treat this as safety-critical. Follow Mitsubishi SRS depowering procedures before touching any yellow connector or seat wiring.
Decode any Mitsubishi Outlander VIN — free recalls, specs & safety ratings — free VIN decoder with NHTSA data
B1C49 Quick Answer
This Mitsubishi-specific code points to an open circuit in the passenger pretensioner squib. The SRS system may disable that pretensioner and keep the airbag warning light on until you find and repair the open.
What Does B1C49 Mean?
Official definition: “Passenger pretensioner squib open.” The SRS ECU detected that the passenger pretensioner igniter circuit does not have continuity or the expected electrical load. In real-world terms, the passenger belt pretensioner may not deploy as designed during a collision, and the SRS light typically stays illuminated.
What the module checks and why it matters: The SRS ECU continuously monitors the pretensioner squib circuit using an internal diagnostic strategy. It looks for an “open” condition, which usually means excessive resistance or a broken path between the ECU and the pretensioner. This matters because the code points to a suspected circuit area, not an automatic pretensioner failure. You must confirm wiring integrity, connector fit, and terminal condition using OEM-approved SRS test methods.
Theory of Operation
Under normal conditions, the SRS ECU monitors the passenger pretensioner squib circuit as part of its readiness checks. The pretensioner contains a pyrotechnic igniter. The ECU only commands deployment during a qualifying crash event. Outside a crash, the ECU uses internal diagnostics to confirm the circuit remains intact.
For B1C49, that normal monitoring sees an “open” state. A loose under-seat connector, damaged seat harness, spread terminals, or corrosion can interrupt continuity. Seat movement often worsens the issue. The ECU then flags the DTC and turns the SRS warning lamp on to indicate reduced restraint capability.
Symptoms
You will usually notice a safety warning first, then you will confirm the fault with an SRS-capable scan tool.
- SRS warning Airbag/SRS indicator stays on or comes on intermittently.
- Passenger restraint reduction Passenger pretensioner may disable until repair.
- Intermittent after seat movement Light changes after sliding the passenger seat.
- Stored DTC B1C49 stores in the SRS ECU memory as current or history.
- Freeze frame clues Event data may show the fault occurred at key-on.
- Failed readiness SRS system may not report “ready” status after self-check.
- Inspection failure Vehicle may fail safety inspection due to SRS lamp.
Common Causes
- Disconnected pretensioner connector: A partially latched seat-side or body-side connector opens the squib loop and the SRS ECU flags an open circuit.
- High resistance in the squib terminals: Light corrosion or terminal spread increases resistance until the module interprets the circuit as open.
- Harness damage under the passenger seat: Seat travel can pinch, stretch, or chafe the pretensioner wiring and break a conductor inside the insulation.
- Wrong seat or belt assembly installed: A mismatched Mitsubishi Outlander component can change the expected squib circuit characteristics and trigger an open fault.
- Loose or contaminated intermediate connector: Dirt, moisture, or poor terminal tension at an in-line connector interrupts current flow in the pretensioner circuit.
- Improper prior repair or aftermarket wiring: Solder joints, butt connectors, or added resistors in SRS wiring often create an unstable connection that reads open.
- Open circuit in the return path: A break in the paired squib wires prevents the ECU from seeing a complete loop, even if one side looks intact.
- Terminal lock or CPA not seated: A missing or unseated connector lock allows micro-movement that opens the circuit during bumps or seat movement.
Diagnosis Steps
Use a scan tool with full Mitsubishi SRS access, OEM service information, and the correct SRS-approved test adapters. Have a DMM for power and ground voltage-drop tests at the SRS ECU feeds. Do not probe squib circuits with standard leads. Depower the SRS system using OEM steps before touching any yellow SRS connector.
- Confirm B1C49 in the SRS menu, not just a global OBD list. Record stored vs pending status and any companion SRS codes. Save freeze frame for battery voltage, ignition state, and vehicle speed. Freeze frame shows conditions when the DTC set. Use a scan tool snapshot later to catch intermittents during seat movement tests.
- Perform a fast visual check before any meter work. Inspect the passenger seat area for recent seat removal, wet carpet, crushed harnesses, or missing connector locks. Verify the harness routing allows full seat travel without tension.
- Check SRS-related fuses and power distribution first. Use the wiring diagram to identify the SRS ECU B+ and IG feeds. Test the fuse load side, not just continuity. A powered fuse can still fail under load with heat or corrosion.
- Verify SRS ECU power and ground integrity with voltage-drop tests under load. Backprobe only at approved locations and follow Mitsubishi procedures. Command the system awake with ignition ON and measure ground drop while the circuit operates. Keep ground drop under 0.1V during operation. High resistance can mimic an open squib fault.
- Depower the SRS system using Mitsubishi’s specified disable procedure and wait the required time. Disconnect the negative battery cable only as directed by service information. Never disconnect SRS connectors with the system powered. Treat all squib circuits as live until you complete the depower process.
- Inspect the passenger pretensioner circuit connectors end-to-end. Check the seat-side pretensioner connector, any in-line connectors, and the body harness connection. Look for bent pins, pushed-back terminals, fretting, moisture, or terminal spread. Confirm CPA/secondary locks fully seat and hold the terminals.
- Use only OEM-approved methods to test the squib loop. If Mitsubishi specifies a dedicated SRS simulator or harness adapter, install it at the correct connector. Do not use a standard ohmmeter directly across an inflator or pretensioner. A simulator lets you check whether the ECU and wiring respond correctly without risking deployment.
- Isolate the fault by dividing the circuit. If the code clears with a simulator at the ECU-side harness but returns with the seat connected, suspect the seat/pretensioner side or its connector. If the code persists with the simulator, suspect the body harness, connector issues closer to the ECU, or an ECU feed/ground problem. Follow the service manual decision tree for exact connector locations, since Mitsubishi routing varies by build.
- Check for intermittent opens tied to seat movement. With the system safely configured per OEM instructions, move the seat through its full travel and gently wiggle the harness at suspected pinch points. Use a scan tool snapshot to capture the moment the circuit status changes. Freeze frame won’t show this because it only captured the original set event.
- Repair the verified issue, then reassemble with all locks installed and proper harness clips in place. Restore SRS power using the OEM sequence. Clear codes with the SRS-capable scan tool and recheck for immediate reset on key-on. A hard open in a continuously monitored circuit typically returns right away.
- Perform a final SRS self-check. Confirm the SRS warning lamp follows the normal prove-out and stays off. Re-scan for any remaining stored or history SRS codes. Document the root cause and the verification steps used.
Professional tip: Many B1C49 comebacks trace to connector handling, not the pretensioner itself. Always confirm the secondary lock engagement and terminal tension. Do that before condemning any seat-belt component. On Mitsubishi platforms, under-seat harness strain from seat track movement creates repeat opens if you do not restore the harness retainers.
Possible Fixes
- Reseat and lock the pretensioner connectors: Fully seat terminals, install the CPA/secondary lock, and secure the connector so seat movement cannot pull on it.
- Repair damaged wiring in the passenger pretensioner circuit: Restore conductor integrity using OEM-approved SRS wiring repair methods and correct routing and retention.
- Clean or replace affected terminals/connectors: Correct terminal spread, remove contamination, and replace connectors that cannot maintain proper tension.
- Correct an incorrect seat or belt assembly installation: Install the proper Mitsubishi-specified pretensioner/seat-belt components and connectors for the vehicle build.
- Restore SRS ECU power/ground integrity: Repair corroded fuse contacts, grounds, or feed connections proven by voltage-drop testing under load.
- Replace the pretensioner/seat-belt assembly only after circuit proof: Replace only when simulator and wiring tests isolate the fault to the component side.
Can I Still Drive With B1C49?
You can usually drive a 2016 Mitsubishi Outlander with B1C49 present, because it does not affect engine power or braking control. Treat the vehicle as having a compromised SRS system. This DTC means the SRS module sees an open circuit in the passenger pretensioner squib loop. That can disable the passenger seat belt pretensioner function in a crash. It can also change how the SRS system manages deployment decisions on Mitsubishi platforms. Do not ignore the warning lamp and do not transport passengers as if full restraint protection works. Do not attempt DIY probing at SRS connectors. Follow Mitsubishi depowering procedures before any inspection near yellow SRS wiring.
How Serious Is This Code?
This code carries high safety significance and low drivability impact. The Outlander will normally start, drive, and shift as usual. The risk shows up in a collision, not during normal driving. With “Passenger pretensioner squib open,” the SRS control unit cannot confirm correct electrical continuity to the passenger pretensioner igniter circuit. The system may disable that output and store a hard fault that keeps the SRS lamp on. You should treat the entire restraint system as potentially compromised until you prove the circuit integrity with OEM-approved methods. Proper diagnosis requires an SRS-capable scan tool, correct depowering steps, and technician training specific to airbag and squib circuits.
Common Misdiagnoses
Technicians often replace the passenger pretensioner or seat belt assembly first, because the code “sounds like a bad pretensioner.” That wastes money when the real problem sits in the seat connector, harness routing, or a partially latched CPA/lock. Another common mistake involves using a standard multimeter or piercing probes on squib circuits. That can damage terminals or violate safe test practices. Some shops also chase a “passenger airbag” problem and miss that this DTC targets the pretensioner squib loop, not the airbag inflator. Avoid guesswork by verifying the open with the scan tool’s SRS data, then confirming connector seating, pin fit, and harness strain points with OEM-approved test adapters.
Most Likely Fix
The most frequently confirmed repair direction for B1C49 on Mitsubishi platforms involves restoring circuit continuity at the passenger seat belt pretensioner connector and harness. That includes correcting a loose connector, damaged terminal tension, corrosion, or harness damage from seat movement. A second common direction involves repairing the under-seat harness routing so it cannot pull on the connector. Do not treat these as certain. Prove the open circuit with proper SRS diagnostics after depowering, and confirm the fault clears and stays cleared after a verified road test under conditions that would normally re-run the SRS self-check.
Repair Costs
SRS/airbag repair costs vary significantly by component. Diagnosis must be performed by a qualified technician with SRS-capable equipment. Do not attempt airbag system repairs without proper training and safety procedures.
| Repair Type | Estimated Cost |
|---|---|
| Professional diagnosis (SRS-certified) | $150 – $250 |
| Wiring / connector / clock spring repair | $100 – $500+ |
| Side airbag / squib module replacement | $400 – $1200+ |
| SRS ECU replacement / reprogramming | $500 – $2000+ |
Key Takeaways
- B1C49 on Mitsubishi: This manufacturer-specific DTC indicates a passenger pretensioner squib circuit open condition.
- Safety first: Depower the SRS using Mitsubishi procedures before touching any SRS wiring or connectors.
- Don’t probe squibs: Use OEM-approved adapters and methods, not standard test leads or back-probing.
- Most causes are wiring: Under-seat connectors, terminal fit, and harness strain points commonly create opens.
- Verify the repair: Confirm the SRS self-check passes and the code does not return after a road test.
FAQ
Does B1C49 mean the passenger pretensioner is bad?
No. B1C49 means the SRS module detects an open circuit in the passenger pretensioner squib loop. An open can come from a loose under-seat connector, poor terminal tension, corrosion, or harness damage. Verify the circuit with Mitsubishi-approved SRS test procedures after depowering the system, then replace parts only after you confirm the root cause.
Is it safe for me to diagnose or repair this at home?
Do not DIY this repair unless you have SRS training, the correct scan tool, and OEM-approved test adapters. Squib circuits require strict depowering steps and handling rules. Incorrect probing methods can damage terminals or create unsafe conditions. If the SRS lamp stays on with B1C49 stored, treat the restraint system as compromised and schedule professional SRS diagnosis.
What are the first physical checks a technician should perform?
Start with a full SRS scan and confirm B1C49 sets as a current fault, not history. Depower the SRS per Mitsubishi steps. Then inspect the passenger seat belt pretensioner connector, CPA/lock engagement, and terminal condition. Next, check harness routing and strain points from seat track movement. Use approved adapters to confirm continuity without probing the igniter directly.
After the repair, how do we confirm B1C49 is truly fixed?
Clear the code only after you complete the repair and reassemble all connectors correctly. Then perform an ignition cycle self-check and verify the SRS lamp behaves normally. Follow with a road test that includes typical seat movement and vibration. Re-scan for current and pending SRS faults. Enable criteria vary by Mitsubishi system, so use service information for exact confirmation steps.
Will I need programming or calibration after fixing a pretensioner squib open?
Programming usually is not required for a wiring or connector repair. If you replace an SRS component, the Outlander may require SRS initialization steps and confirmation with a scan tool that supports Mitsubishi SRS functions. Some systems also store event data that changes replacement rules after a deployment. Use Mitsubishi service information and an SRS-capable scan tool to complete verification.