How to reset Toyota Airbag SRS Computer Crash Data

How to: reset Toyota Airbag SRS Computer Crash Data. 

Step 1: Introduction
The airbag computer controls the supplemental restraint system in your vehicle, including the airbag sensors, inflators and seat belt pretensioners. It also acts as a black box when you get into a major collision that involved.

Step 2: Airbag Computer's Cannot Be Reused
Well if you decide to rebuild the vehicle and replace the airbags:

You need to replace the SRS computer, since it has a hard code inside that can’t be erased and you’ll be stuck with an airbag light on:

You won’t even be able to access the SRS computer using Toyota techstream software either.

Step 3: Remove the Airbag Computer

The airbag computer is located underneath the dashboard. The bottom half needs to be removed to access it.

Disconnect battery before working on SRS system

Step 4: Disasemble the Airbag Computer
Airbag computer removed:

Open up the computer:

We’re looking for this 8 pin SMD EEPROM chip here that stores the crash data, it says L56R on it

Step 5: Solder and Hookup to an EEPROM Reader
Solder some 32 gauge hookup wire to connect it to the serial
port EEPROM reader (lots of EEPROM reader options, CG100 is best for Japanese car airbag reset)

I built a little EEPROM reader using some resistors and diodes:

Here’s the setup, with the airbag computer EEPROM going to the reader, and then the reader going to the serial port directly on a legacy Pentium 4 computer. You can also purchase USB EEPROM readers

Step 6: Analyze Crash Data
Then I used PonyProg software which is a serial device programmer to read from the EEPROM chip:

Here’s what the crash data looks like:

From a clean, uncrashed Corolla, I dumped the information from its SRS computer and it looks like this:

Comparing the two, you can see a lot of data values have changed.

So now I’m going to replace all the values from the crashed chip with those from the virgin chip and rewrite it to the computer to clear the hard code. Then I’ll replace it into the vehicle

Step 7: Replace the Airbag Computer
So now I’m going to replace all the values from the crashed chip with those from the virgin chip and rewrite it to the computer to clear the hard code. Then I’ll replace it into the vehicle

Step 8: Test to Make Sure It Works
The SRS light should go out within 6 seconds if everything
is functioning normally. I also double checked it with Toyota techstream software and there aren’t any codes or faults found.

And It works!. 

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