parts ids

[car enthusiast]

Update, the parts have been id'd. Thanks.

 

[Diver300]

The tall components are attached to the lid to stop them vibrating. The capacitors only have two pins so they can wobble from side to side and break the legs.

Some restraint control modules charge capacitors up to a high voltage so that more energy can be stored. The energy has to be stored as the airbags may need to be fired after the battery voltage has been lost.

The UAA1280T is obsolete and I can't find it's data sheet so I don't know what it does, or why two are needed.

 

[rjenkinsgb]

The UAA1280T ICs are dedicated airbag controllers; Mouser used to sell them at one time..

https://eu.mouser.com/ProductDetail/NXP-Semiconductors/UAA1280T-V1?qs=wUVvLa%2FZKxV1FYxW0fxUjA%3D%3D

One of the large block items may be a supercapacitor to store the energy to fire the airbag detonators?

The TLC2274 is a fairly common quad opamp.

Some of the other numbers are probably "in house" codes, likely custom made or custom programmed devices made/programmed for one specific system manufacturer and not otherwise available with that programming.

 

[car enthusiast]

Thanks guys.

 

[Diver300]

A steel ball-in-tube accelerometer will probably rattle if shaken, or at least some movement could be felt.

I don't know what the UAA1280T ICs do, but ECUs usually have a microcontroller with low power outputs, and separate ICs are used to operate high-power signals.

The 52 pin device would be the microcontroller, which contains the CPU and the memories, so that is normally where data would be stored. The simpler ICs would probably not store any information.

It's difficult to know what the different capacitors are used for. There are often one or two electrolytic capacitors across the 12 V power supply.

I don't known what the 6 pin device is. A better photo might help.

The quad op-amp isn't likely to drive the ignitors, as it doesn't have enough power. It's more likely to be sensing acceleration from an analogue output accelerometer. It's common to have op-amps as separate components because it's rare to get op-amps inside microcontrollers, and I certainly wasn't common 20 years ago when that module was designed.

 

[car enthusiast]

Your answers help a lot!

 

[rjenkinsgb]

I believe the UAA1280T ICs combine the airbag circuit continuity monitoring and power switching to fire the airbags.

The connections to the CPU will likely just be logic level and analog signals for control and fault detection.

I'd expect a more capable power source than the normal electrolytics, for the firing power? I may be wrong, but I'd guess a supercap..

 

[car enthusiast]

Excellent. This dovetails with the processing scatter-referenced throughout the Shop Manual. Thank you.

 

[narkeleptk]

The MCU is a MC68HC705, It has eeprom where config data, dtc's and crash data is stored. As well as a rom for the programming (read only)

Im guessing this is from a hyundai? I dont know many older hyundai srs modules so Im not sure what that tube is in yours but in a lot of other airbag modules they will have similar tubes with a large cap inside it. If its not that I guess it could be some type of tilt switch to detect roll over but I dont usually see these inside of airbag modules so Id be a bit surprised. Should be pretty easy to test with a dmm.

 

[car enthusiast]

Good call on the Hyundai.

Thanks!

 

[car enthusiast]

Thanks.

 

[narkeleptk]

Good call on the Hyundai. What indicated that to you?

And how did you map the main ECU #s to the Motorola MC68HC705?

- You called it a SRSCM . Thats Hyundai talk.
-I work with it all the time in airbag modules and immobilizers. The 0D69J gives it away.

 

[rjenkinsgb]

The SA20 is an accelerometer:

Figure 6. The SA20 airbag accelerometer, 1992.

Download scientific diagram | The SA20 airbag accelerometer, 1992. from publication: From research to industry | Today SensoNor is a major supplier of high volume MEMS products to the automotive industry and well recognized for high product reliability. However, the "Si-sensor story" in Horten...

www.researchgate.net

 

[car enthusiast]

Good to know.

The 0D # was 0D60J.

 

[car enthusiast]

Wow, great find on the SA20! Huge thanks for that!

 

[narkeleptk]

Good to know.

The 0D # was 0D60J. What MC # would that be? That would be different, right?

The # on the chip started with Z and ended with CFN, but the intervening sequence was covered by the QC sticker.

Yea sorry I miss read it. 0D60J is MC68HC05B16

 

[car enthusiast]

Hearty thanks to Diver300, rjenkingsgb, and narkeleptk for their answers and for their time and knowledge and guidance.