Unable to Get VIN Number response from OBD-2 Device

Question

I need to fetch VIN number from car's controller using plxKiwi-2 wifi obd2 device. I am getting other information like car rpm,speed,throttle position,etc. in correct format. But when I request for VIN Number it gives me below response.

014 0: 49 02 01 FF FF FF 1: FF FF FF FF FF FF FF 2: FF FF FF FF FF FF FF

which is invalid.In Hyundai's EON car, I got proper response for VIN Number,but in almost all other cars, I got above mentioned response. So is there any specific 'AT' command to get the proper VIN response ?? Please help.

Thurmond

Answer 1

After lot of searching, I came to the conclusion that it is not necessary that all the cars will respond its VIN Number.

It depends on the manufacturer whether he wants to disclose the Chassis number or not. So I was in the proper direction and was able to read VIN Number from many of the cars but not from all.

Hence,

• NO DATA

For New Cars (Protocol Number > 5 , i.e. CAN Protocol)

• 014 0: 49 02 01 FF FF FF 1: FF FF FF FF FF FF FF 2: FF FF FF FF FF FF FF
• 014 0: 49 02 01 xx xx xx 1: xx xx xx xx xx xx xx 2: xx xx xx xx xx xx xx

And for Old Cars (Protocol Number <= 5 , i.e. NON-CAN Protocol supported cars)

• 49 02 xx xx xx xx xx 49 02 xx xx xx xx xx 49 02 xx xx xx xx xx 49 02 xx xx xx xx xx 49 02 xx xx xx xx xx

responses are some of the valid responses ... And if we get VIN response from ECU, please cross-check that VIN number's length is exactly 17- alphanumeric characters.

Thurmond

How to convert this to the actual VIN number? – Glossematics

@perozzo What are you getting in your 09 02 response? It also depends on Car's manufacturer. All manufacturers have different VIN number format – Thurmond

Thanks for the comment. I have already managed to format the answer to the correct VIN number. – Glossematics

Answer 2

Already read the question, and had no idea ready. But since you've asked me to check it out, I'm going to give it a shot. You send the command 09 02 right?

You can check with command 09 00 which commands in the VIN-mode (09 xx) are supported. You will get this bit-encoded answer from the car, and with that answer you can check if 09 02 is supported. (If you need help with the bit-encoding, please ask help, but it's not very hard with some googling). Looking forward if this match with your 09 02 reports.

Most likely it will not be supported, and that will be the problem.

I believe there is no AT command available to get the VIN, you need to use mode 09.

Edit 1: Now I'm thinking about it, and it could be protocol related, but I have to do way much google-work to find that out. Might be an option to find out which protocols work for your VIN-reading.

Luciferous

Hey @Eric thanks for the reply. I have already checked for supported PIDs of Mode-09. In that response, I am getting '1' (Set Flag) for pid-02 , it means that it supports VIN Number. – Thurmond

Answer 3

There is no mistake. You send the command "09 02" and the ECU replies with a positive response "49 ...". Indeed, it is strange that instead of getting the real vin you receive "0xFF...", but this is normal for Hyundai cars. I have seen this before in Hyundai vehicles - response with all bytes "0xFF".

Kneehigh

I ran an ios program (ezobd) and it works fine on all cars that support 0902 obd command except for two, a 2003 and 2004 ford 1 ton 4x4. On those trucks I get all Fs. I get the same Fs from a Ford VCM II profesional scanner. – Cowherb