Read how to test the check engine light, but I have a, will crank, and no spark situation. Turn the ignition key on and all warning lights are on except for the check engine light. Put pin in #6 or #2 and press button light will come on strong when depressed hold a second and let go and then I will get no flashes. It appears i cannot comunicate with the ECM.. could it be a bad ECM or some other fuse or relay... THanks for any help.. Greg.

 

Welcome to the forum.

This link will take you to a full how-to use the diagnostic system including what to do if it doesn't flash. Scroll down to pages 5 & 6.

http://www.matthewsvolvosite.com/for...c&start=12

It does apply to your car although headed for the '92 740 turbo.