Is there a way to test the 7way trailer plug with a multimeter on the 2015 and up trucks?

I thought that with the 15 & up truck these all have the 'smart' tow plugs which detect when a trailer is connected. With that the plugs dont have power until a trailer is connected meaning there's no power and so you cant test them with multimeter. maybe 7way testing plug is the only way? surely not.

anyone help on this?

my issue, 2015 xlt with tow package, factory plug connections, and the driver side brake/turn signal light isnt working. same light is on for the running lights but doesnt light up for brake/turn. its LED if that makes a difference. all other lights function as they should. this makes me think its not a ground wire issue, not a fuse issue bc both L & R turn/brake lights work off the same fuse. Also, camper lights worked just fine on another vehicle, so its got to be a problem with the truck somewhere. Need to get this fixed asap, leaving on a trip in less than a week.

 

A DTC scan using FORScan or a diagnostic scan tool could be helpful in determining the cause of the problem. The TRM has several DTCs that it can issue to add in diagnostics.

 

 

Thanks. problem already solved.

 

So, please complete this thread a let us know what the problem was.

 

I bought a test plug from Oreilly. problem was the plug connections, not the truck recepticle.

 

Thank you. This may help others with the same issue.

 

For the SMART System to detect a trailer connected, the trailer has to complete the circuits to reference ground for the continuity tests it detects..
If the Trailer wiring is not correct to standard, the Test unit will not light up the LED for each circuit.
A voltmeter test is not the same action for testing. it does not draw current of enough consequence because the Voltmeter résistance is too high.

A plug-in test tool has LEDs that will be detected because they reference signal ground to light up and draw enough current, the same as a Trailer circuits accomplish..