I have got this problem after flashing 
https://bitcointalk.org/index.php?topic=236875.msg3045417#msg3045417
What is your miner version? If the rear lights are blinking, it's testing for the frequency. Depending on the modes, heavy testing or light, the time to init will take less than a minute and mainly 1 sec if you choose to run light test on them. Once the init is done, the front light will be on.https://bitcointalk.org/index.php?topic=236875.msg3045417#msg3045417
Once the front light blinks, it means it's hashing...
The rear LEDs are all off now after flashing, only LED1 (power) rear led works.
There was 2 rear leds working before flashing (LED7 and LED8 I think)
Front LED always blinking now (2-3 time per second) even when the cgminer not started.