Installing racing seats can significantly enhance the aesthetics and feel of your vehicle, offering improved support and a sporty touch. However, a common issue encountered after swapping out stock seats is the persistent and often irritating Air Bag Light illuminating on your dashboard. This guide, brought to you by obd-de.com’s auto repair experts, will walk you through the process of resolving this problem efficiently and safely.
Understanding the Air Bag Light Issue
The dreaded air bag light, often depicted as a seated figure with a deployed airbag, signals a malfunction within your car’s Supplemental Restraint System (SRS). In many modern vehicles, including models like the Nissan 370z discussed in the original article, the factory seats are equipped with side airbags. These airbags are crucial for safety, deploying in side-impact collisions to protect the occupants.
When you replace your original seats with racing seats, you typically disconnect the electrical connectors linked to these seat-mounted airbags. This disconnection disrupts the SRS circuit, causing the system to register a fault and illuminate the air bag light. The vehicle’s computer detects the missing airbags and, as a safety precaution, activates the warning light.
It’s important to understand that driving with the air bag light on means your entire SRS system might be compromised. While the car is still drivable, other airbags in your vehicle might not deploy correctly in an accident if the system is indicating a fault. Therefore, addressing the air bag light issue isn’t just about clearing a dashboard annoyance; it’s about ensuring your vehicle’s safety systems function as intended.
This guide will present two primary solutions to tackle the air bag light problem. The first, and most common, involves using resistors to simulate the presence of the original seat airbags, effectively turning off the warning light. The second, more involved solution, focuses on retaining the functionality of the passenger weight sensor, which is relevant for passenger airbag deployment based on weight detection.
Solution 1: The Resistor Fix for Air Bag Light
This method is a straightforward and effective way to eliminate the air bag light when you’ve removed your stock seats with airbags. By installing resistors, you’re essentially tricking the car’s SRS system into thinking the airbags are still connected.
Supplies You’ll Need
Before you begin, gather the necessary tools and components:
- (2) 4.7 Ohm, 1/2 Watt Resistors: You’ll need one resistor for each seat where you’ve disconnected the airbag connector. These resistors mimic the electrical load of the original airbags.
- Wire Stripper: To expose the wires for connection.
- Soldering Iron & Solder (Recommended): Soldering provides a robust and reliable electrical connection.
- Heat Shrink Tubing (Recommended): To insulate and protect the soldered connections.
- Electrical Butt Connectors (Alternative): For those who prefer not to solder, butt connectors offer a crimp-on alternative.
- Wire Crimper (If using Butt Connectors): To securely crimp the butt connectors.
- Electrical Tape (Alternative): If heat shrink tubing isn’t available, electrical tape can be used for insulation, though heat shrink is more durable.
- Helping Hands or Third Hand Tool (Suggested): This tool can be very helpful in holding wires and components steady during soldering.
Image alt text: A collection of tools and electronic components laid out on a workbench, including resistors, wire strippers, soldering iron, heat shrink tubing, and electrical connectors, representing the supplies needed for an air bag light fix after installing racing seats.
Step-by-Step Guide: Installing Resistors
Safety First: Before starting any electrical work on your vehicle, it is highly recommended to disconnect the negative terminal of your car battery. This will prevent any accidental electrical shorts or issues during the process.
-
Locate and Cut the SRS Connector: Find the electrical connector under your stock seat that was disconnected when you installed the racing seat. This is the SRS connector, usually identifiable by yellow tape or housing. It’s advisable to retrieve your original stock seats if they are not readily accessible in your vehicle. Cut off the connector from the seat side, leaving a few inches of wire attached to the connector itself. Do this for both the driver and passenger side connectors.
-
Prepare the Wires: Unwrap any yellow tape from the connector and carefully strip a small portion of insulation from the ends of the wires on the connector.
Image alt text: A close-up of a stripped electrical connector from a stock car seat, showing the exposed copper wires ready to be connected to a resistor for an air bag light fix.
-
Solder or Crimp the Resistor:
-
Soldering (Recommended): If you are soldering, place the connector in a helping hands tool to keep it steady. Wrap one end of a 4.7 Ohm resistor around one of the exposed wires of the connector. Heat the wire from underneath with your soldering iron and apply solder to the top of the connection. Ensure the solder flows smoothly and creates a shiny, solid joint. Repeat this for the other end of the resistor and the remaining wire on the connector, forming a loop with the resistor.
Image alt text: The process of soldering a resistor onto the wires of a car seat connector to bypass the air bag sensor and resolve the air bag light issue after aftermarket seat installation.
-
Butt Connectors (Alternative): If using butt connectors, crimp a butt connector to each wire of the connector. Then, insert the leads of the resistor into the butt connectors and crimp them securely.
-
-
Insulate the Connection:
-
Heat Shrink Tubing (Recommended): Slide a piece of heat shrink tubing over the soldered resistor connection before soldering the second lead. After soldering both leads, slide the tubing to cover the entire connection and use a heat gun or hairdryer to shrink the tubing for a secure and insulated finish. For extra protection, you can use a larger piece of heat shrink tubing to cover both connections together.
-
Electrical Tape (Alternative): If using electrical tape, tightly wrap the tape around each resistor lead and connector wire connection individually, ensuring complete insulation.
Image alt text: A completed resistor installation on a car seat connector, showing the resistor soldered to the wires and insulated with heat shrink tubing, effectively simulating an air bag for the system.
-
-
Repeat for the Other Seat: Perform steps 1-4 for the other seat’s SRS connector.
-
Reconnect and Reset: Reconnect the modified connectors under your racing seats. You will then need to perform an air bag system reset procedure to turn off the air bag light. The exact reset procedure can vary depending on your car model. For some Nissan models, it may involve a specific sequence of turning the ignition on and off. Consult your vehicle’s repair manual or search online for the “air bag reset trick” specific to your car model.
Solution 2: Retaining Passenger Weight Sensor Functionality (Optional)
For vehicles equipped with a passenger weight sensor, simply installing resistors will address the air bag light related to the seat airbags, but it will not reinstate the functionality of the passenger weight sensor. This sensor determines if a passenger is heavy enough to warrant airbag deployment in a collision. If you wish to retain this feature, especially if you frequently have passengers, this section outlines how to relocate the sensor to your racing seat.
Why Retain the Passenger Weight Sensor?
The passenger weight sensor is a safety feature designed to prevent unnecessary airbag deployment when a child or a light object occupies the passenger seat. Retaining this functionality ensures that the passenger airbag will only deploy when an adult or a sufficiently heavy occupant is in the seat, optimizing safety and potentially reducing repair costs after minor accidents where a passenger airbag deployment might be excessive.
Caution: If you choose to bypass or disable the weight sensor functionality (for example, by always having the passenger airbag armed), NEVER install a forward-facing child seat in the front passenger seat. In an accident, the forceful deployment of the airbag could seriously injure or even fatally harm a child.
Supplies for Weight Sensor Relocation
- Ratchet with 3/8″ drive
- 12mm Socket
- 6″ Extension for Ratchet
- Small Cable Ties (15+): To re-secure the seat fabric.
- Needle Nose Pliers or Needle Nose Vice Grips: To handle small rings and cable ties.
Image alt text: Underside of a car passenger seat, highlighting the location of bolts that need to be removed to access the passenger weight sensor for relocation to a racing seat.
Step-by-Step Guide: Relocating the Weight Sensor
-
Remove the Seat Bottom Pad: On the underside of your passenger stock seat, locate and remove the four 12mm bolts that secure the lower seat pad to the seat frame. These are typically marked with a small number ‘7’.
Image alt text: A detailed view of the underside of a car seat, focusing on the 12mm bolts that need to be unscrewed to detach the bottom seat pad and gain access to the weight sensor.
Image alt text: An alternative angle showing the location of a 12mm bolt on the underside of a car seat, emphasizing the specific type of bolt that secures the bottom pad for weight sensor access.
-
Detach the Seat Pad Fabric: Once the seat pad is loose, turn it over to access the underside. Use needle nose pliers to disconnect the weight sensor wire from any plastic clips holding it to the seat pad. Then, find the small metal rings securing the fabric to the seat foam and frame. Using your pliers, twist and unravel these rings to release the fabric. You will discard these metal rings. Carefully peel back the fabric to expose the weight sensor.
-
Remove the Weight Sensor: The weight sensor is attached to the seat pad in a similar fashion to the fabric, using metal rings. Twist and remove these rings to detach the weight sensor, being careful not to damage the sensor itself. Set the sensor aside.
Image alt text: A passenger airbag weight sensor detached from the car seat pad, after removing the fabric covering and metal rings, ready for relocation or bypass to resolve the air bag light.
-
Re-upholster the Stock Seat Pad: Reattach the fabric to the seat foam using small cable ties in place of the metal rings. Thread the cable ties through the fabric holes and around the metal rods in the foam, pulling the fabric taut and securing it with the cable ties. Trim the excess cable tie length and rotate the trimmed edge inwards for a neat finish. Reattach the seat bottom pad back onto the seat frame using the 12mm bolts.
-
Install Weight Sensor in Racing Seat: Place the passenger weight sensor inside your racing seat, ideally under the center pad if your seat has a removable pad. Fish the sensor’s electrical connector through the back of the seat and connect it to the car’s wiring harness under the seat.
If your racing seat does not have a removable center pad, you can place the weight sensor underneath the racing seat, flipped upside down (white side facing up). In this orientation, the sensor will typically always register a weight, and the passenger airbag will always be armed.
Image alt text: The passenger airbag weight sensor positioned within a Bride racing seat, placed under the seat pad and connected, demonstrating how to retain the sensor functionality after installing aftermarket seats.
Image alt text: A Bride racing seat with the seat pad placed back over the passenger airbag weight sensor, showing the sensor concealed and integrated into the racing seat setup for continued passenger weight detection.
Final Steps: After completing either the resistor fix or the weight sensor relocation (or both), ensure all connections are secure and perform the air bag system reset procedure for your vehicle to clear the air bag light.
Disclaimer: Modifying your vehicle’s SRS system carries inherent risks. This guide is for informational purposes and intended for use by individuals with experience in automotive electrical systems. If you are not comfortable performing these modifications yourself, it is strongly recommended to consult a qualified automotive technician. obd-de.com and the author are not responsible for any damage or injury resulting from the use or misuse of this guide. Always prioritize safety and ensure all work is carried out with caution and a thorough understanding of your vehicle’s systems.
