I had a contact sensor connected to a bridge on a camera. It was working OK but but the signal was a little week and it didnt always change status when the door opened or closed. I recently installed another camera which is closer to the contact sensor so I wanted to pair it with the new camera and bridge. I tried doing the normal push the reset and wait for 3 flashes of the LED but it flashed 5 times and the flashes were faster than the normal 3 setup flashes and it wouldnt connect to the bridge. I removed the battery and waited for 15 minutes and then reinstalled - when I pushed the reset I get the same 5 quick flashes and it wont connect to the bridge. Tried several times but every time I push the reset I get the same 5 quick flashes and it wont connect.
Is there anything I have to do different to connect a sensor to a different bridge.
You put the sensor on a different camera correct. Are you selecting the correct camera?
I’d try and do a hard reboot on the new cam with bridge.
When the bridge turn solid blue try again.
Also install a new branded battery in the sensor are known to go weak factory cheapies.
I had the same issue with two of my sensors. They are used on an out-building and barn, which are not temp-controlled. I found that if I connected the sensor when the outdoor temp was similar to an indoor temp, they connected easily. If outdoor temps were extremely hot or cold, it took 20+ tries to get them connect.
I am having same issue with my garage door mounted sensor. Battery for it died a month back. So today I popped open the cover and put a new Sony battery. But as my app still showed it offline, I removed device from app and trying to repair, but it just wont. I got fedup and got the second unused one from box and paired that and it instantly paired. Put that back up on garage door, but still want to get the old one working. I also moved the bridge to a second v2 cam that i have the newer no person detection firmware as the help webpages say to check if cam has latest firmware. Still no luck. Rebooted this cam, still nothing. I do see the 3 or 4 time flashing of light on sensor when I insert pin in reset hole. I have checked the battery with a multimeter and it shows 3.15 volts so it is charged. My cam is indoor, sensor has now been indoor as well for over 30 mins. Will leave it indoor and try again after sometime.
Contact Sensor I take it? I’ve been having problems with about three of mine going off-line and I cannot get them for anything to reconnect. I’m about ready to submit a ticket
Yes, Contact sensor. As this happened today, I was checking for solutions on forum first.
Will open a ticket soon. As this thing gives so little info, I dont have high hopes. The electronics in them does not last.
Remove sensor from the app … clear cache in account/app settings.
Remove the bridge, reboot the cam first then reinstall the bridge.
Take out the battery for a couple of days sometimes fixes the issue… I did it with one and it worked after pairing.
There are test points on the inside of the sensor but not sure if shortening them out or which ones to in which it might reset the sensor …IDK.
Tried all, did not work.
On Reset of sensor. I get 5 times led flash instead of 3 as they say in pairing instructions.
Battery was already dead in this for a month, before I removed it and put new battery
I will now remove new battery, put it back in box, open a support ticket. Try again after few days.
I’m having this exact same problem with one of my sensors. Was working fine, then battery died so I replaced it. Now it won’t pair, even after deleting it from the app.
If in warranty, contact support. They ask few things to debug and then send a replacement. Not worth their techs time to debug a $3 item a lot.
I purchased 4 sensors at the same time, and two (pair from same box) failed to reconnect after battery failure. One flashed 5x red light when attempting to pair, the other had no light, even with brand-new (confirmed working) battery installed. I contacted tech-support and they replaced both of them under warranty. Best I can tell, they had a bad batch that brick once the battery dies. The other pair are either newer or older than the other two, and they are working perfectly, even after battery swaps.
Contact support and open a ticket. If they are under warranty, they will replace them… no problems!
Same issue with mine, but live in Canada, so no warranty. 
Any update on an actual official fix for this?
I have opened a ticket as well, but was just given a general checklist of “make sures”
Anyone have luck with support in getting their sensors to pair again after battery replacement? If so, what steps did you take?
Same problem here, but I live in Brazil
Same problem here. Indonesia, import form Amazon, so no warranty. Problem happened after replacing battery. Am waiting some good news here…
Update: Got replacement contact sensors from Wyze, under warranty. They paired immediately with my bridge. Literally in less than 5 seconds. So the issue I think is definitely gonna be with the old contact sensors themselves, not the camera or the bridge.