I have a GE smart timer 15086 I followed the instruction and the light blinks when you turn it on. Please help

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

Wiring instructions and on-line manual appear on following link.
http://waterheatertimer.org/GE-timers-and-manuals.html#15071

I have tested this timer, but I'm not there to test it out for you.
Let me offer a troubleshoot list how I would start.
1) Switch located behind timer door that says OFF-TIMER. Make sure it is set to Timer.
2) 4 square buttons located behind timer door that sit in each corner. These are override buttons, and should turn lights on-off. Push each one separately.
3) Check wiring against instructions shown on link above. This timer will not operate unless wired correctly.
4) Ground wire broken off? Each cable that enters a box can be pulled a bit further so maybe you can grab some of the ground.
The ground is not critical for timer operation -UNLESS- you are using it to power electronic clock inside timer.
Normally white neutral wire is used for clock electronics, as described in wiring instructions.
5) Conflicts in programming. If 7-day programming has conflicting days or hours, timer will not operate as expected.
Check programming.
6) Reset timer and start over.
7) I test timers, and some arrive defective. GE makes a good timer, manufacturing timers for many decades: 15086 is sold at Home Depot. Buy another one and take back defective one.

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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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I am guessing that you have digital in-wall timer GE 15071 or GE 15086

To identify timer for sure, see images at following link:
http://waterheatertimer.org/GE-timers-and-manuals.html#15071

Manual for 15086
http://waterheatertimer.org/pdf/GE-15086-Manual.pdf

If this is new timer, the problem could be a couple things.
1) Circuit has electrical problem that is affecting timer electronics.
Use circuit analyzer from Home Depot electric department and test any receptacle on same circuit breaker as timer.
2) event1 ON was programmed but event1 OFF was not programmed. To review events, press Prog button once to see event1 ON and press Prog button again to see event1 OFF. When review is complete, press clock key to return to current time.
3) event1 ON and event1 OFF are programmed with conflicting day schedules
4) event1 and event7 have conflicting schedules

If this is new or old timer:
5) Timer needs to be reset because of internal glitch. Press and hold reset button for a moment and timer display will start flashing 12:00 am MO
6) These timers can go bad any time. I test timers and 4-6% arrive defective, and most quit after couple years, but some can last quite a while. This is why I suggest using a circuit analyzer to check if circuit is causing difficulties.

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.

GE 15086 manual
http://waterheatertimer.org/pdf/GE-15086-Manual.pdf

GE 15086 manual:
http://waterheatertimer.org/pdf/GE-15086-Manual.pdf

Sounds like you connected white wire incorrectly, or are trying to replace 3-way switch.
GE 15071 and 15086 are for single-pole switch replacement only, and will not work for 3-way.
Open following page for correct wiring of GE in-wall timers, and for list of timers used for 3-way.
http://waterheatertimer.org/GE-timers-and-manuals.html#15071

If you have different timer, add a comment with in-focus photo of your timer for correct identification and possible assistance.
http://www.fixya.com/support/r6568559-post_photograph_fixya_questions_answers

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Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

Open link below to see wiring instructions and manual:
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

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Also take advantage of fixya phone service.
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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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Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on timer or any do-it-yourself project.
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