I have a double switch box controlling inside lights and outside lights. I installed a GE Smart Digital Timer (model 15086) to control the outside lights. In the wall box, the white wires are tied together as are the ground wires. The single black wire from the panel branches with one branch feeding the manual switch controlling the inside lights, and the other branch feeding the timer to the outside lights. The timer works fine until I switch on the inside lights. When the inside lights are on, the timer will turn on the outside lights randomly. Once on they stay on until I hit the switch on the timer to turn them off. Then they will come on again at random times. By "random" I mean that the outside lights may come on immediately when I switch on the inside lights, or they may take 2, 3, 4, or 5 minutes to come on. I can switch the outside lights off repeatedly and as long as the inside lights are on they will come back on again at some time. I paid $30 for this timer and would like to avoid having to buy another one. How can I correct this? Thanks!!

http://www.manualsdir.com/models/ge/in-wall-15086-ge-smart-digital-timer.html

I test timers, and no damage is done.
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

Sounds like you wired red and white wires together, or installed timer in place of 3-way switch.
15086 will not replace a 3-way switch.
For example, when 2 switches control hallway light, that is 3-way.
Link above has list of timers that replace 3-way switch.

How to wire 15071, 15086, 15265, 15266 timers:
1) Switch has 2 insulated wires. Take switch wires and connect them to timer-black-wire and timer-red-wire. Choose either one for now.
2) In back of electric box are white wires twisted together and covered with wire nut. Connect timer-white to these wires. This will power timer electronics.
3) If electric box does not have white wires described above, then connect timer-white to bare ground, along with timer-green wire.
4) Turn on electricity, and push ON-OFF button located in each corner. If lights come on, timer is wired correctly. If lights do not come on, then reverse timer-red and timer-black wires.

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15086 timer:
Pressing door will override timer setting and manually turn switch ON-OFF.
Press door or open timer door, and press any of 4 buttons located in corners.
You know information posted so far:

However, you are moving the small switch from Timer to OFF.
And when switch is OFF, the override does not work because circuit is OFF.
You want a timer that can switch programming OFF, and not switch circuit OFF, so that device toggles between timer and ordinary switch.

Looking at timers on the market today, I cannot think of any in-wall programmable or box timer that does what you want. Each has manual override that reverses timer function, but when you set timer to OFF, the circuit is OFF.
http://waterheatertimer.org/Programmable.html#Aube

Plug-in-type timers have override button that turns programming off, and then you can operate table lamp normally with the lamp switch. But in that case, the lamp has separate switch that operates outside of timer functions.

GE 15070 24-hour mechanical timer could do what you want:
http://waterheatertimer.org/images/GE-15070-mechanical-timer.jpg
In this specific case, when you wanted to operate timer like a light switch, you would move all the pins inward, and then use the on-off switch. The problem with this idea is the pins are tiny, and you need very good eyes or a light-source and small tool to continually adjust pins.

See GE timers and manuals:
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

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Here is how to wire that timer:
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

1) Timer green wire connects to bare ground wire.
2) Switch has 2 insulated wires. Take switch wires and connect them to timer-black-wire and timer-red-wire. Choose either one for now.
3) In back of electric box are white wires twisted together and covered with wire nut. Connect timer-white to these wires. This will power timer electronics.
4) If electric box does not have white wires described above, then connect timer-white to bare ground, along with timer-green wire.
5) Turn on electricity, and push ON-OFF button located in each corner. If lights come on, timer is wired correctly. If lights do not come on, then reverse timer-red and timer-black wires.

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The 15086 is a straight timer, so it should work with no problems. CFL bulbs only have problems when run off a photocell switch/timer or a dimmer circuit.

Woods timers:
http://waterheatertimer.org/Woods-timers-and-manuals.html
Scroll down page to make sure your timer is shown.
You posted under Woods 59018-59028

GE 15086 timer has OFF-Timer switch
http://waterheatertimer.org/images/GE-15086-programmable.jpg
http://waterheatertimer.org/Programmable.html#Aube
Add a comment to identify timer, and I can help more

Double-check wiring:
1) Timer-green-wire connects to bare ground wire.
2) Switch has 2 wires. Take switch wires and connect them to timer-black-wire and timer-red-wire. Choose either one for now.
3) In back of electric box are white wires twisted together and covered with wire nut. Connect timer-white to these wires.
4) If electric box does not have white wires described above, then connect timer-white to bare ground.
5) Turn on electricity, and push ON-OFF button. If lights come on, timer is wired correctly. If lights do not come on, then reverse timer-red and timer-black wires.

http://www.manualsdir.com/manuals/400481/ge-in-wall-15086-ge-smart-digital-timer.html

I think this is the dealy timer you have installed and if your relay is connected to the other side it becomes and switched on timer.
So I think if the timer controller is correct you must connect the lamp to the OFF relay and when the door is opened the lamp wil light up for the designated time set.
Is that so?

This timer requires a neutral wire, it may or may not be present in the back of your box as a group of wire nutted whites. It is NOT the single white switch leg.

GE 15086 can replace single pole switch only.
If you have "3-way" switch, that is when 2 switches control same light, for example in a hallway.

Open link below to identify GE15086 timer, see wiring instructions, on-line manual <> and see list of timers that can be used for 3-way switching with links to those timers and manuals:
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

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