Re: Decoding Trouble Code on ABS

--- In opendiag@yahoogroups.com, "smogman1002000"
<smogman1002000@y...> wrote:
> hello everyone,
>
> I have been sniffing around on my 2002 VW Beetle ABS using Jeff
> interface along with VB6.
>
> Here are the result.
>
> Tx: 84 28 F1 18 02 FF 00 B6
>
> 84 28 F1 = HEADERS
> 18 02 FF 00 = UNKNOWN
> B6 = CHECKSUM
> '''''''''''''''''''''''''''''''''''''''''''
>
> Rx: 94 F1 28 58 06 04 14 60 01 1F 6C 01 22 6C 01 1D 6C 01 1B 6C 05
22
> 64 3B
>
> 94 F1 28 = HEADERS
> 58 = UNKNOWN
> 06 = # OF CODES (MAYBE)
> 04 14 = CODE 01044 (CONVERTED HEX TO DECIMAL)
> 60 = UNKNOWN
> 01 1F = CODE 00287
> 6C = UNKNOWN
> 01 22 = CODE 00290
> 6C = UNKNOWN
> 01 1D = CODE 00285
> 6C = UNKNOWN
> 01 1B = CODE 00283
> 6C = UNKNOWN
> 05 22 = CODE 01314
> 64 = UNKNOWN
> 3B = CHECKSUM
>
> If someone can explained what those UNKNOWN Bytes mean.
>
> Thanks,
>
> Isaac

Hi...

The 58 is the positive Answer Sign from ABS ECU (0x18+0x40)...

The other unknown bytes are the status byte of each fault code.
You have to divide them into HighByte and LowByte and then the parts
into binary.

Example 64 => HB=6, LB=4 Convert to binary:
6=0110 4=0100

First Bit of HighByte signs, MIL OFF/ON
Second and Third Bit of HighByte signs Fault code status (Test
incomplete, static code ...)
4th Bit of HighByte signs Test for this fault code running or
complete

The LowByte descibes the fault condition
First Bit of LowByte means incorrect signal
Second Bit of LowByte means no signal
Third Bit of LowByte means below threashold
4th Bit of LowByte means upper threashold

Greets

Tobias

 
Received on Mon May 23 22:48:28 2005