110v power outlet, not working

Hello, I have a 2009 tacoma t that we bought used we have not used the outlet in these bed until this weekend, we tried to plug in a air mattress pump to blow up the.bed and it would not work, the lights on the dash switch come on when you push it but go out as soon as you let off and no power. If you hold the switch the lights stay on for a second and than still go out. Is there a fuse or relay I can check before taking it to the dealer? Also the power demand of the little pump says .9 amps. Thanks

 

check the proper fuses as well as the AC relay under the hood.