REVELTRONICS

Hello,

I've been using a RevelProg IS for some time now and it works great. I'm trying to read a 93..86 series eeprom that I believe has 16 bit data. The data should contain VIN numbers for a Subaru but it doesn't appear to. Am I pulling it off in the wrong format or something?

I've attached a bin file of what I'm getting.

Thanks!

It looks like file is corrupted, many reapated values. Do you reading it in adapter/socket or in circuit? If you reading it in circuit please read it in socket, maybe there is other ongoing transmission (e.g. between eeprom and mcu) where you are trying read it in circuit and there is bus conflict

Hello ArT,

Thanks for your reply. I am reading it in circuit and at 3.3v. I don't have the ability to remove the chip and read it in socket. Is there any way to get it to read in circuit? I have attached a photo of the board and circled the chip I'm trying to read.

If I remember correctly I've seen where possibly discharging the capacitors on the board could help in this situation. Is that true?

Thanks!

What voltage is on chip when you connect power supply to ECU? I'm asking because 93xx series are usually for 5V and 3v3 maybe to low. You can try with higher voltage but first you need to make sure that all chips around will be fine with higher voltage. But if you have bus conflict (MCU is communicating with eeprom as fast as you connect power supply to it) then it's nothing you can do - only disconnecting eeprom from board. Discharging capacitors won't help, when you connect power supply to eeprom it will power all circuit around (connected to the same power line). I recommend to identify this chip exactly and check what voltage range is required for read/write - some 93xx needs minimum 4.5V, some 93xx allows programming as low as 2.5 volts - depends on variant and manufacturer. It's quite easy to desolder this chip with hotair gun, a lot of space around

Hello,

I tried different voltages but none seemed to work. It looks like desoldering is the only option at this point.

Thanks for your help!