This is a trace image:
It looks like you are using the Siemens product sequence, which should work fine, but you need the original DWI images (these derived maps are automatically computed by the scanner by default, but it can be turned off in the protocol card). The raw DWI will have lower series number and the ImageType tag should look like:
(0008,0008) CS [ORIGINAL\PRIMARY\DIFFUSION\NONE\ND\MOSAIC] # 42, 6 ImageType
(it might not say MOSAIC at the end, but it needs to say ORIGINAL\PRIMARY)