1999-2000 Mitsubishi Galant Air Bag Module: Side Airbag Compatibility and Replacement Guide

Symptoms of a Failing Air Bag Control Module

The most common and obvious sign of a problem with the airbag system is the SRS warning light on your dashboard. When you start your car, this light should illuminate for about seven seconds as part of a system self-check and then turn off. If the light stays on, flashes, or never comes on at all, it indicates a fault within the system.

• Persistent SRS Light: A continuously lit SRS or airbag warning light is the primary indicator that the control module has detected a fault and has disabled the airbag system.
• No Communication with Scan Tool: A professional diagnostic scan tool may be unable to communicate with the airbag control module, pointing to an internal failure or power supply issue.
• Fault Codes Stored: An OBD-II scanner capable of reading SRS codes can retrieve specific Diagnostic Trouble Codes (DTCs). Codes like B1400 (ECU Malfunction) or others indicating communication errors or internal faults point directly to a bad module.
• Intermittent Electrical Issues: In some cases, a failing module can cause strange electrical problems, such as other warning lights appearing randomly or unexpected battery drain, though this is less common.

Known Issues, Recalls, and Technical Service Bulletins (TSBs)

While no recalls directly target the airbag control module for the 1999-2000 Mitsubishi Galant, several recalls for this period involve related electrical systems and airbag components that are important to be aware of.

• NHTSA Recall 99V333001: This recall addresses a battery cable wiring harness that can suffer heat damage from the exhaust manifold on V6 models. This could lead to grounded circuits, potentially affecting various electrical systems.
• Takata NADI Inflator Recalls: While the Galant is not specifically listed, many Mitsubishi vehicles from this era (like the Montero) were part of a massive recall for non-azide driver inflators (NADI) made by Takata. These inflators could rupture or underinflate. It is wise to check your vehicle's VIN on the NHTSA website to ensure no open recalls apply.

No specific Technical Service Bulletins (TSBs) for widespread failure of the airbag control module on this specific model were found in public databases. Most issues are diagnosed on a case-by-case basis by troubleshooting the specific SRS fault code.

Buying a Used Air Bag Control Module: A Buyer's Guide

Purchasing a used airbag control module can be a cost-effective solution, but it requires careful attention to detail to ensure safety and compatibility. For the 1999-2000 Galant, there is one critical factor to verify.

The Side Airbag Requirement

How to Verify Compatibility and Condition

1. Match the Part Number Exactly: The only way to guarantee compatibility is to match the OEM part number on your original module to the number on the replacement unit. The primary part number is MR359158. Do not rely on visual similarity alone.
2. Verify Vehicle History: Only purchase a module from a reputable recycler who can guarantee the part was sourced from a vehicle that did not have its airbags deployed. A module from a crashed car will have "crash data" stored and will be locked, rendering it useless without a specialized reset.
3. Physical Inspection: Before installation, inspect the used module for any signs of damage. Look for corrosion on the electrical pins, signs of water intrusion (discoloration, rust), or any indication that the case has been opened or tampered with.

Programming and Installation Requirements

For the 1999-2000 Mitsubishi Galant, replacing the airbag control module with a used unit that has the exact same part number and comes from a non-crashed vehicle is typically a plug-and-play procedure.

• No VIN Programming Required: When you use the correct, original-equipment module, you should not need to perform any VIN programming or visit a dealer.
• Clearing Fault Codes: After installation, the SRS warning light will likely remain on. You will need a diagnostic scan tool capable of reading and clearing SRS codes to turn the light off and finalize the repair. A standard engine code reader will not work.

Can I Reset My Old Module Instead of Replacing It?

If your original module is faulty due to internal errors (not physical damage like from a flood) or has stored crash data after an accident, you can often have it professionally reset. This service involves a specialist clearing the crash data and hard codes from the module's memory, restoring it to factory condition. This is significantly cheaper than buying a new module and guarantees you are using the original part programmed for your car.

Replacement Overview

Replacing the airbag control module is a moderately difficult job that requires care and precision. The module is located under the center floor console assembly, between the two front seats.

1. DISCONNECT THE BATTERY: This is the most critical safety step. Disconnect the negative battery terminal and wait at least 10-15 minutes before beginning any work on the SRS system. This allows the system's backup power to discharge, preventing accidental deployment of the airbags.
2. Access the Module: You will need to remove the center console trim and components to gain access to the module.
3. Unbolt and Unplug: Carefully disconnect the electrical connectors (they are typically yellow) and unbolt the module from the vehicle floor.
4. Install the New Module: Bolt the replacement module in place, reconnect the wiring harnesses, and reassemble the console.
5. Reconnect Battery and Clear Codes: After everything is reassembled, reconnect the battery. Turn the ignition on and use an SRS-capable scan tool to clear any stored fault codes.

Cost Breakdown

Prices can vary based on supplier and location. Here is a general estimate of what you can expect to pay:

Frequently Asked Questions (FAQ)