Will Disconnecting the Battery Reset the Airbag light?

Disconnecting the battery to reset the airbag light is not a guaranteed or permanent fix.

The light may still come back on if an underlying issue persists. It will also reset other things in the car, such as the clock and radio. You’ll have to adjust their settings again after reconnecting the battery. But you may find other electrical issues crop up as well. So, what’s the best way to reset the airbag light?

indicates airbag light on — Video | Mr Technic

First, check the SRS-ACM(Airbag Control Module), battery, airbag sensor, SRS wiring, seat belt tensioners, and clock spring. Only then try the battery disconnection method.

Resetting the airbag light by disconnecting the battery is a straightforward process. You turn off the ignition, disconnect the battery, and wait 15 minutes. Then, reconnect the battery and turn the ignition back on. It should be reset.

If resetting the battery doesn’t work, you can use an OBD-II scanner to clear the fault code or manually remove the fuse for a while. If the issue persists, take your vehicle to an auto-electrician.

An Airbag Light Issue

a light indicating an airbag issue — Video | Auto Repair Guys

The airbag light is part of the vehicle’s SRS (Supplemental Restraint System).

It serves as a warning indicator of a problem with the airbags. It should only illuminate momentarily when first starting the car. It should then turn off, but it indicates an issue if it remains on, flashes, or suddenly turns on while driving.

You shouldn’t ignore an airbag light issue.

The airbag should always be available for your safety in the event of a collision. You must, therefore, fix this issue right away.

Possible Causes

The airbag light usually comes on for any one or more of the following reasons:

A problem with the SRS-ACM (SRS’s Airbag Control Module). It has a small battery that powers the airbag system to ensure it can deploy the airbags in the event of a collision.
A problem with the airbag system’s sensor. The sensor is responsible for detecting a collision. If a collision occurs, it sends a signal to the ACM to instantly deploy the airbags. A malfunctioned sensor will be unable to perform this operation.
A problem with the airbag system’s wiring can also cause the airbag light to come on.
A malfunctioned SRS-ACM cannot receive the sensor’s signals to determine whether to deploy the airbags correctly. It might be due to an electrical or software issue, exposure to moisture, or physical damage.
Other causes – A problem with the seat belt tensioners or clock spring. The latter is a spiral cable that maintains the electrical connections between the steering wheel and the airbag system.

First Solutions to Try

So, before disconnecting the battery or trying one of the other alternative methods to reset an airbag light, make sure:

The SRS-ACM’s battery is not weak, as that might be the cause of the airbag light coming on. Replace it if it is.
The airbag sensor and SRS wiring are not physically damaged. Check them and have them replaced if they are.
The SRS-ACM is free of moisture and not physically damaged. Dry it, if necessary, or replace it if it’s damaged.
Have the seat belt tensioners and clock spring checked. Repair or replace them if damaged.

Video | ChrisFix

It is relatively inexpensive if you need to replace the airbag’s sensor or wiring. But replacing a malfunctioned ACM would be more expensive.

Resetting an Airbag Light by Disconnecting the Battery

If the above solutions didn’t work, here are the steps to reset an airbag light by disconnecting the battery:

Step 1: Turn Ignition Off

Turn the ignition off and remove the key from it.

Step 2: Disconnect the Battery

Open the vehicle’s bonnet (or hood) and locate the battery.

detaching/disconnecting battery — Video | The Home Depot

Loosen the cable using a wrench or spanner. Detach the black wire from the battery’s negative terminal and the red wire from its positive terminal.

Step 3: Wait 15 Minutes

Wait for at least 15 minutes before reconnecting the battery.

Step 4: Reconnect the Battery

Reattach the black wire to the battery’s negative terminal and the red wire to its positive terminal.

Tighten the cable using a wrench or spanner.

Step 5: Turn Ignition On

Insert the key into the ignition and turn it on.

See if the airbag light turns off (after the momentary illumination) or remains on.

airbag lights turn off — Video | Mr Technic

Note that even if the airbag light turns off this time, it might come back on later. If so, you will need to investigate further, as there is likely to be an underlying issue you must resolve.

But there are two more methods you can also try to reset the airbag light:

Using an OBD-II scanner
Manual resetting

Alternative I: Using an OBD-II Scanner

The first alternative method requires using an OBD-II scanner.

An OBD-II scanner is a diagnostic tool that reads and clears the carputer’s fault codes. Here’s how to do that:

Step 1: Locate the OBD-II Port

Firstly, locate the OBD-II port on the car’s computer. The carputer is usually located under the dashboard on the driver’s side.

Step 2: Plug the OBD-II Scanner

Plug the OBD-II scanner into the OBD-II port.

Step 3: Turn the Ignition On

Turn the ignition on without starting the engine.

Step 4: Read and Clear the Codes

Read the airbag system-related fault codes by following the instructions on the OBD-II scanner’s display. Then, clear the codes.

The airbag light should turn off once the fault code is cleared. If it doesn’t, you can try turning it off manually.