Hi all,
I'm looking for what kind of hash / checksum / srs is being used to the following 16bit datas without success.
They come from a communication between diagnostic tool and Boshc engine control unit.
The message flow are the follow:

Diag. Tool:  0x02 0x27 0x01 0x00 0x00 0x00 0x00 0x00  Request for security access
Ecu         :  0x04 0x67 0x01 0xPh 0xPl 0xaa 0xaa 0xaa  where 0x04 are the lenght of message, 0x67 = 0x27+0x40, Ph Pl are plain data H and L
Diag. Tool:  0x04 0x67 0x02 0xCh 0xCl 0x00 0x00 0x00  where Ch and Cl are the checksum or crypted data related to Ph and Pl

I've obtained the response of the tool feeding message with only one bit set for Ph and Pl, but with no result.

Ph Pl         Ch Cl
00 01        42 88
00 02        82 80
00 04        02 5F
00 08        01 D4
00 10        FF 9D
00 20        F6 B1
00 40        D2 D9
00 80        43 29
01 00        03 C7
02 00        04 FE
04 00        07 5A
08 00        0B CA
10 00        13 8A
20 00        1E 8A
40 00        22 8A
80 00        E2 89

This are general values from ecu<->tool communication:
Ph Pl         Ch Cl
8C E9        39 97
D9 F6        61 33
BF C7        67 25
85 B2        00 ED
42 51        1B B0
F7 BD        1C 27
DA 89        27 3D
B1 27        28 8E
AF 6E        2A 71
BE 51        3F 5E
68 AD        4C 2A
DC C4        5B 47
06 01        5F 62
71 9A        7A 6F
71 7D        83 4D
42 1D        8E 08
6B FA        A2 83
63 A0        AA B6
6E 57        BC 73
E6 EB        E5 5B
A4 07        E8 37
A2 AD        EA BA
9E 2A        F5 FA
25 D1        F9 53

Hope someone better than me in decryption can give an help...
Thank you in advance.

Kornelio

Hi, these are all the information I can give you:
End Model Part Number: 8983702321
Software Version Number: 2
Hardware Part Number: 8983337470
Sys. Supplier ID/ECU Hardware Number: BOSCH0100
Base Model Part Number: 10C0386E
Diagnostic Data Identifier: 2302
MEC: 0
Interchange Ability Number: 11BOSCH001
Ecu Address: 11

Thank you for any information!

Kornelio

Hi, there's a Bosch code in thevusual form:

0 281 032 814

This is the engine control unit of new Isuzu DMax and truck model M21.
For both veichles the engine code is rz4e

Kornelio