[Shazbat]

I have a 2007 Honda Odyssey (44k miles). Last night my son unlocked the driver's door with the key rather than the fob/remote. He then opened the passenger door with the driver's door UNLOCK switch. We both got in the car and fastened our seat belts, when I noticed the flashing red light on the dash. Before I could comment that the light should not be on, he started the car. Immedietly, the horn started honking and flashers started flashing. I tried to reset the alarm with the key fob - no luck. The electrical UNLOCK switches also did nothing (did not even lock/unlock the doors!). I ended up pulling the ground wire from the battery. I hoped to reset whatever had happened. This morning, as soon as I connected the battery, the horn started sounding.

So, does anyone have a clue where I should start troubleshooting? It seems the Alarm logic is off as well. Shouldn't the alarm have started sounding when the door was opened? Certainly not when the ignition is energized!

Any help is greatly appreciated!

 

[1001Jim]

https://techinfo.honda.com/rjanisis/pubs/om/HH0707/HH0707O00146A.pdf

 

[Unique]

Happened to me once . i had to exit the vehicle re lock the doors with the key then activate the alarm w/remote. Then deactivate it with the remote and it was fixed. I hope this helps.

PS: make sure all wires are reconnected before attempting this.

 

[Shazbat]

Thanks for the responses. After looking all through the Service Manual, to no avail, I spoke with the service department at a local dealer. He agreed with me that the logic sequence seemed off, but that a reset should be possible. He said to make sure all the doors were closed and either attempt a reset with the remote control (lock, unlock, lock, unlock) or by turning the ignition switch to the on (position ii), off, on, off, on with 5 seconds.

So, I reconnected the battery, the horn started blasting again, and I turned the key to on, off,on,off,on.....the horn stopped in mid-blast!

In respect for my neighbors, I didn't try setting off the alarm again to test the remote.

As this appears to be a non-published reset technique, it may be valuable to remember!

Thanks again to all on this forum. It is my go-to source of reference, sometimes before I even check the Service Manaual!

 

[mb99zz]

I have a 2008 Odyssey EX-L and the described solution (off/position-2/off/position-2…) did not work for me. I saw that mentioned on several forums and in the security user guide...but it wouldn't work on my van. The good news is that something else did and I hope this is helpful for anyone in the same predicament. In my situation, the alarm on the van was going off and the key fob/remote was no longer working (it took an unplanned trip through the washing machine the day before the alarm mishap).

A friend was trying to help trouble-shoot the issue and found a post online that worked for us. Not that I think it matters, but I’ll start by saying that we had disconnected the negative terminal on the battery to stop the alarm for some peace and quiet. We would reconnect the terminal each time we wanted to try a new fix.

The trick that worked for us was using the key in the driver’s side door. To be specific, I went into the van and manually locked all of the doors (front and sliding doors). This was while the battery was still disconnected. I then exited the car and shut the driver door. So, all doors were shut and locked. My buddy then reconnected the negative wire to the battery. The horn promptly started blaring and the anti-theft light blinked on the dash. I then inserted the key into the driver’s door lock and turned it to the left to manually unlock the door. The horn immediately stopped blaring and the anti-theft light on the dash stopped blinking. Problem solved.

I hope this helps anyone searching for a similar problem! Good luck!!!