Can someone suggest a good cleaning product for the S40 non-leather seats?

 

Are you planning to use an extraction machine to clean the fabric or just spray and wipe?

 

Just spray and wipe was the idea.

 

I have used 409 to clean fabric in cars with great success. It has even taken ink out. You just need to test it on an inconspicuous area first. If you can rent one I recommend an extraction cleaner since it will suck the dirt out and you can scotchguard at the same time. They usually rent these machines at Home depot or supermarkets.