I am working on this lg gas double oven thats only 4 years old . Everything works but the bottom oven . When bake is selected, the oven interior lights blink a slow pulse and will run for about 30-40 seconds without lighting , then oven will shut off as it beeps its finish tune . No error codes are shown. I replaced the main control board ,and still it does same thing . Any pointers and comments are greatly appreciated !!!