horn honk on r/s shutsown 04 trailblazer

  I recently installed an ultrastart 4270 in this rig with a gmdl-bp(omega version). Everything is working great, only there is a minor issue that doesn't affect the way the r/s works, just annoying. When the r/s is shut down via remote, or brake pedal, or is timed out the horn will honk on the trailblazer and the doors lock. Is there any way to stop this from happening? Thanks for the input in advancejmacf14

Does the trailblazer sound the horn during normal locking/arming of the vehicle? Or do you have to hit lock a few times before it sounds the horn?Steve G

unhook the horn....or check the programing

The manual says....for negative horn output, or pos(+) siren output. It appears you get to choose. I would disconnect the output from the horn. Look at menu 1 setting #2

Thanks for the replies. None of the outputs from the alarm are connected to the horn at all. I think it is the bypass module or something else. It only happens at r/s shutdown. It doesn't happen when you r/s and get in the rig and turn the key to run and push the brake. Only on shut down from remote or from brake pedal input w/o the key on run. the horn doesn't honk at any other time. only the r/s siren will chirp as it should be.jmacf14

The bypass does cause a horn honk when rearming the factory security. You can use a timed relay to break the horn connection temporarily while it rearms. http://www.directechs.com/techtips/pdfs/resources/security/directed_techtips/1054.pdfSteve G

now I am having another issue with this trailblazer. It doesn't do this all the time only 3out of 5 , but the alarm will sound after the doors lock and alarm arms. It happens after the dome lights go out. weird! Anyone see this before?jmacf14

Which alarm sounds the factory one or the ultra?

never seen it be intermittent, but that horn honk and lock is a feature of the pgmdlbp that you used.

xtremej wrote: Which alarm sounds the factory one or the ultra?

  It is the ultra that goes off. and like I mentioned it is not all of the time.jmacf14