I have a dgat056bdc furnace with Blend air deluxe ii in a mobile home, that short cycles,the fan on top ,upper control board and hsi have been replaced,jumped the red and white wire on t-stat and nothing happens.And have a solid green on the hsi module.

Intermittently my furnace will not "heat up". Thermostat calls for heat and I can hear it kick on but it won't heat up. Blower motor will sometimes come on and blow cold air, sometimes not. Seems like it starts to ignite the gas for a few seconds and then it clicks off. This doesn't happen all the time but it seems to have started doing this more in the last week. It does seem to have a harder time starting early in the morning when it is coldest. Not sure if that is true, maybe we just notice it not turning on more when it's cold. [url=https://youtu.be/RDcoPB7u6e4]Here is a video I took this morning.[/url] The blue flame stays on for about 5 secs then shuts off. Then the yellow/orange (pilot light?) fades away slowly. It stays dark for about 45 seconds and then repeats exactly the same. It probably did this 7 times in a row before I shut it off at the thermostat. Any thing I can check on my own first before calling someone out? Thank you.