J Relay vs Yellow relay difference

[ProjectS90]

Hi.

On my 1998 S90 project I see on the inside cabinet fuse box J label relays and also I see them in fuse/relay box under the hood. In the owners manuals all the relays in fuse/relay box under the hood shows J label relays. When I check the box under the car hood I see a mixture of yellow relays and j relays. Im having trouble finding J relays on line and the options I get are generic relays when I do a search for a replacement. Someone knows what’s is the difference of a J relay vs a yellow relay? Should all J relays where the manual illustrates that a j relay goes there should have a j relay?

Thanks

Ed