B1109 Code - Diagnosis Sensor Unit
Quick Answer
The Air Bag Diagnosis Sensor Unit detects the whole SRS electrical system and displays the malfunction either by illuminating or blinking the air bag warning lamp in the combination meter. Common causes include Faulty Diagnosis Sensor Unit, Diagnosis Sensor Unit harness is open or shorted, Diagnosis Sensor Unit circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- B1109 indicates Diagnosis Sensor Unit.
- Common causes
- Common causes include Faulty Diagnosis Sensor Unit, Diagnosis Sensor Unit harness is open or shorted, Diagnosis Sensor Unit circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code B1109 Description
The Air Bag Diagnosis Sensor Unit contains the “G†sensors for both frontal and side collisions and spare battery function in case of main battery damaged in a collision.
What are the Possible Causes of the DTC B1109?
- Faulty Diagnosis Sensor Unit
- Diagnosis Sensor Unit harness is open or shorted
- Diagnosis Sensor Unit circuit poor electrical connection
How to Fix the DTC B1109?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B1109 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- B1109 Ford — Passenger Door Central Locking Motor Commanded Position Not Reachable
- B1109 Infiniti — Diagnosis Sensor Unit
- B1109 Lincoln — Passenger Door Central Locking Motor Commanded Position Not Reachable
- B1109 Mercury — Passenger Door Central Locking Motor Commanded Position Not Reachable
- B1109 Nissan — Diagnosis Sensor Unit
Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service
- Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
- Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
- Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
- Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.
Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.
Frequently Asked Questions about B1109 Code
1. What are the common symptoms of OBDII code B1109 (Diagnosis Sensor Unit)?
- Common symptoms include malfunction indicator light (MIL) illumination, trouble shifting gears, and issues with the transmission system.
2. What are the possible causes of OBDII code B1109?
- The code B1109 can be triggered by a faulty diagnosis sensor unit, damaged wiring or connectors, or issues with the transmission control module.
3. How can I diagnose OBDII code B1109?
- Diagnosis of code B1109 typically involves using an OBDII scanner to retrieve the code, inspecting the diagnosis sensor unit, checking the wiring and connectors for damage, and testing the transmission control module.
4. Can I continue driving with OBDII code B1109 present?
- It is not recommended to continue driving with OBDII code B1109 present, as it can lead to further damage to the transmission system and potentially unsafe driving conditions.
5. How can I repair OBDII code B1109?
- Repairing OBDII code B1109 usually involves replacing the faulty diagnosis sensor unit, repairing or replacing damaged wiring or connectors, and reprogramming or replacing the transmission control module if necessary.
6. Are there any DIY tips for fixing OBDII code B1109?
- While some basic inspections and tests can be done by DIY enthusiasts, repairing OBDII code B1109 often requires specialized tools and expertise, so it is recommended to consult a professional mechanic for proper diagnosis and repair.
7. Is OBDII code B1109 specific to a certain vehicle make or model?
- OBDII code B1109 can appear in various vehicle makes and models that are equipped with OBDII systems, especially those with automatic transmission systems.
8. What are the potential risks of ignoring OBDII code B1109?
- Ignoring OBDII code B1109 can lead to worsening transmission issues, reduced fuel efficiency, and potential safety hazards due to unexpected transmission failures.
9. Can a faulty diagnosis sensor unit cause other OBDII codes to appear?
- Yes, a faulty diagnosis sensor unit can cause other related OBDII codes to appear, such as codes related to transmission control module malfunctions or sensor failures.
10. How much does it typically cost to repair OBDII code B1109?
- The cost of repairing OBDII code B1109 can vary depending on the extent of the issue, parts needed, labor costs, and whether any additional repairs are required. It is recommended to get a professional estimate for an accurate cost assessment.
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