No charging light on magsafe, how do I test with multimeter

My magsafe charger light is not coming on. How can I test it and troubleshoot this not charging.

crwdns2893858:0crwdne2893858:0 crwdns2893862:0crwdne2893862:0

crwdns2894050:0crwdne2894050:0

crwdns2889612:0crwdne2889612:0 0
crwdns2892346:0crwdne2892346:0