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26 Posts
Discussion Starter · #1 ·
Need help diagnosing airbag. There is no diagnostic connector in the SRS airbag wiring diagram. But there are two wires going to the instrument panel from the SRS module.
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Is the SRS diagnostic in the instrument cluster or not? Does each item need to be checked separately?

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26 Posts
Discussion Starter · #3 ·
Thanks for your interest in the topic. This car does not have a wire connecting the Air bags control module to the OBD port. Only the Driver's information panel has an extra wire.
In many cars of these years, diagnostics took place through the Driver's information panel, you only need to know the secret combination of buttons.
Or is there a mistake in the diagram?
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26 Posts
Discussion Starter · #5 ·
Thanks for the tips, I've taken your advice.
Today I dismantled the Air bags control module and OBD port.
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Indeed, there is a diagnostic wire on the 54pin to the 3pin OBD port.
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I checked with an oscilloscope how the module works.
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This is how the Passenger presence sensor works
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This is how Passenger's seat belt pre-tensioner unit works

Found out that Passenger presence sensor and Driver's seat belt warning switch are not working.
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They probably wanted to turn off the seat belt system, but they broke the Air bags.

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26 Posts
Discussion Starter · #10 ·
Thanks for support.
I tilted the seat, in the passenger I see a cut wire, in the driver's seat there are damaged wires and a seat belt module.
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I can't get the seat out of the car, it's too heavy. I want to remove the back cover.
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The second hour I read the manual, I can not find how to disassemble the seat.

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26 Posts
Discussion Starter · #12 ·
Removed the rear seat cover. Found an unknown device connected to the interface.
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Inside the device was a diode and a resistor.
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I restored the wire, checked the sensor in the seat.
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The sensor works but needs to be calibrated.
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I tried to fix the belt buckle. Someone connected it bypassing the interface.
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Looks like a problem with the sensor in the lock.

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26 Posts
Discussion Starter · #13 ·
Dismantled the interface. There are two resistors inside. There is nothing to break here.
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Dismantled the seat belt module. Hall sensor inside.
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The sensor is filled with plastic, heated it for a long time and gently to remove the plastic. Inside the sensor and two transistors.
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While warming, all the details fell off. Soldered back, put a new Hall sensor - it works.
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The breakdown occurred because the soldering fell off from time.
I don’t understand why this car has such a complicated design. I do not remember another car with such a 4-wire sensor.
How to fix it?
Buy a new seat belt module for $1100?
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