When a vehicle is rebuilt after a collision involving airbag deployment, the airbag computer must be replaced. Here’s a video on how to clear the crash data from the airbag computer and reprogram it with clean virgin data.
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 airbag deployment.
Let’s say you get into a collision with your beige Corolla.
And your airbags deploy:
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’s techstream software either:
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:
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:
Solder some 32 gauge hookup wire to connect it to the serial port EEPROM reader:
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:
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:
The SRS light should go out within 6 seconds if everything is functioning normally. I also double checked it with Toyota’s techstream software and there aren’t any codes or faults found.
It works!
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 airbag deployment.
Let’s say you get into a collision with your beige Corolla.
And your airbags deploy:
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’s techstream software either:
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:
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:
Solder some 32 gauge hookup wire to connect it to the serial port EEPROM reader:
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:
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:
The SRS light should go out within 6 seconds if everything is functioning normally. I also double checked it with Toyota’s techstream software and there aren’t any codes or faults found.
It works!