Driver door ajar alarm keeps going on and off as I am driving and the door locks keep clicking on and off. This only happened occasionally, I sprayed WD-40 in lock area and it stopped for a few weeks. Now, they just keep going on and off. The horn also will randomly go off now when truck is parked and off.

The latch striker post needs to be adjusted. check for broken plastic roller on the post.

first I would be looking at the body switches for dirt or rust causing a false signal.. then I would adjust the part of the alarm that the wind affects..it should be adjustable for sensitivity..the dealer service should be able to advise you..if not check with an alarm service company..that installs these systems..good luck..

You need to have the Body Control Module scanned to determine the cause here, guess work won't solve the probem.

You need the dealer to scan the Body control module while this is happening, i think you have a defective door ajar switch here.

It's in the driver door most likely do you have keyless entry and do you use your key to punch in the #s if so the seal is broken and letting water in if not the driver door module deals with all and also the door wire that's at the latch lock where you close the door that wire could be breaking making the interior and door ajar light comes on but all problems are in the driver door your master lock control keyless entry and alarm and door ajar all go through the driver door module check for moisture in it or corroded connections and broken wires also have fuses checked for blown ones have fun in your techno boogie box and if you do use your key press the key pad buttons get out of the habit

it sounds like you have a door open that is why the light is on. it may not be a actual open door but a faulty door ajar switch. that would explain why the alarm keeps going off. i would start by opening and shutting all doors includingthe hood and hatch.
if that does not fix it-a gm dealer with a tech 2 scanner should be able to located which door ajar switch is bad.

spray your door lock with dw40. sounds like the sensor in your door frame is not making correct contact. look on your door frame. all door frames. and see if you can spot any torn rubber or anything that could cause the sensor to not correctly close

you may have a broke wire in the door harness

spray the door latch with WD - 40 on both doors then open and close multiple times. Sometimes they get stuck ond this help if they free up once a month should keep it away

There is a micro switch in the door latch thats faulty. I believe you must replace the latch assy.