VIN decoding, Check Digit Help

[PAUL SS]

I just searched for VIN decoding and found some very good information. What I was not able to locate was how the check digit works or how to decode or figure what it means. Anybody have this info?

[heinzd01]

Can you read VBA? If so, I can PM you a function that returns the checksum digit.

1 - Each character of the VIN must be translated to a number except for the 9th character.

2 - Each number from 1 above is multiplied by a weight factor for each position of the VIN.

3 - The values from 2 above are summed.

4 - The value from 3 is divided by 11

5 - The modulus from 4 is the checksum character unless it results in a 10 in which case X is used.

[PAUL SS]

Can I read VBA? I am lucky to be able to have a picture of my SS in my sig. What the heck is VBA?

[heinzd01]

Originally Posted by Paul SS

Can I read VBA? I am lucky to be able to have a picture of my SS in my sig. What the heck is VBA?

VBA = Visual Basic for Applications. If you have Microsoft Office products installed (Excel, Word, Access, Outlook, etc), you should be able to use VBA.

 
'====================================================================================================
' PURPOSE:  Calculate checksum chacter 9 of VIN
'====================================================================================================
Function VIN_Checksum(strVIN As String) As String
10        On Error GoTo ErrorTrap
          Dim n As Integer
          Dim int_VINChar As Integer
          Dim lng_VINCheckSum As Long
 
20        lng_VINCheckSum = 0
 
30        For n = 1 To Len(strVIN)
 
              ' 1 - Translate each VIN character to a number
40            Select Case Mid(strVIN, n, 1)
                  Case "0"
50                    int_VINChar = 0
60                Case "1"
70                    int_VINChar = 1
80                Case "2"
90                    int_VINChar = 2
100               Case "3"
110                   int_VINChar = 3
120               Case "4"
130                   int_VINChar = 4
140               Case "5"
150                   int_VINChar = 5
160               Case "6"
170                   int_VINChar = 6
180               Case "7"
190                   int_VINChar = 7
200               Case "8"
210                   int_VINChar = 8
220               Case "9"
230                   int_VINChar = 9
240               Case "A"
250                   int_VINChar = 1
260               Case "B"
270                   int_VINChar = 2
280               Case "C"
290                   int_VINChar = 3
300               Case "D"
310                   int_VINChar = 4
320               Case "E"
330                   int_VINChar = 5
340               Case "F"
350                   int_VINChar = 6
360               Case "G"
370                   int_VINChar = 7
380               Case "H"
390                   int_VINChar = 8
400               Case "J"
410                   int_VINChar = 1
420               Case "K"
430                   int_VINChar = 2
440               Case "L"
450                   int_VINChar = 3
460               Case "M"
470                   int_VINChar = 4
480               Case "N"
490                   int_VINChar = 5
500               Case "P"
510                   int_VINChar = 7
520               Case "R"
530                   int_VINChar = 9
540               Case "S"
550                   int_VINChar = 2
560               Case "T"
570                   int_VINChar = 3
580               Case "U"
590                   int_VINChar = 4
600               Case "V"
610                   int_VINChar = 5
620               Case "W"
630                   int_VINChar = 6
640               Case "X"
650                   int_VINChar = 7
660               Case "Y"
670                   int_VINChar = 8
680               Case "Z"
690                   int_VINChar = 9
700           End Select
 
              ' 2 - Multiply number from 1 by a weight factor
710           Select Case n
                  Case 1
720                   int_VINChar = int_VINChar * 8
730               Case 2
740                   int_VINChar = int_VINChar * 7
750               Case 3
760                   int_VINChar = int_VINChar * 6
770               Case 4
780                   int_VINChar = int_VINChar * 5
790               Case 5
800                   int_VINChar = int_VINChar * 4
810               Case 6
820                   int_VINChar = int_VINChar * 3
830               Case 7
840                   int_VINChar = int_VINChar * 2
850               Case 8
860                   int_VINChar = int_VINChar * 10
870               Case 9
880                   int_VINChar = int_VINChar * 0
890               Case 10
900                   int_VINChar = int_VINChar * 9
910               Case 11
920                   int_VINChar = int_VINChar * 8
930               Case 12
940                   int_VINChar = int_VINChar * 7
950               Case 13
960                   int_VINChar = int_VINChar * 6
970               Case 14
980                   int_VINChar = int_VINChar * 5
990               Case 15
1000                  int_VINChar = int_VINChar * 4
1010              Case 16
1020                  int_VINChar = int_VINChar * 3
1030              Case 17
1040                  int_VINChar = int_VINChar * 2
1050          End Select
 
              ' 3 - Sum all the multiplied values from above
1060          lng_VINCheckSum = lng_VINCheckSum + int_VINChar
1070      Next n
 
          ' 4 - Divide the sum from by 11 and get the remainder
1080      lng_VINCheckSum = lng_VINCheckSum Mod 11
 
          ' 5 - Convert the remainder to text and return a value to the calling function
1090      If lng_VINCheckSum = 10 Then
1100          VIN_Checksum = "X"
1110      Else
1120          VIN_Checksum = CStr(lng_VINCheckSum)
1130      End If
1140      Exit Function
 
ErrorTrap:
1150      mstr_SubProcedure = "VIN_Checksum"
1160      Log_Message 1, "ERROR", mstr_SubProcedure & " line: " & Erl & "; Error: " & Err.Number & " " & Err.Description
End Function        ' Function VIN_Checksum(strVIN As String) As String

[UCF w00t]

Originally Posted by Paul SS

I just searched for VIN decoding and found some very good information. What I was not able to locate was how the check digit works or how to decode or figure what it means. Anybody have this info?

Basically, it's used to verify the VIN to see if there was an error in it. If one of the digits were mistakenly copied down, the VIN will (most likely) have an invalid check digit. To Joe Schmo, it's pretty useless. But to anyone writing a program to do something with VINs, it's a bit complex but extremely cool.

[PAUL SS]

Thanks, that answered my question, but it's way over my head. My check digit will be known when the car is produced.