All dash lights on except check engine?

Hello! I'm finally posting on this forum. I'm not much of a computer person myself but always enjoyed all the info on this site.
I've been a van owner for 6years. Toured with bands, camped, drove across the counrty twice!!
I own 3 vans! No I'm not addicted 😬
1987 4wd auto
1985 2wd 5sp
1985 2wd auto
All Gray!!!
I've done all my own work on them since the begining. This probelm is stumping me.
Every dash light is on except check engine light?
I did a check engine test the light flashes 11 code.
So the bulb works. Ecu? Voltage is 13.9 alternator? Is that xmas lights? Battery reads 11.7 not running.
Tranny is all messed. Won't shift until very high rpms(automatic). I was working on changing the kick down cable. Then this started. Any way that's all I can tell you about this problem.
Thanks
Keep on Vanning

Assuming your engine is running when all the lights are on then yes, that is Christmas dash. Your check engine light is grounded through the computer and should only be on for bulb test before starting the engine or when there is an active code. The rest of the warning lights have a dual ground circuit with the alternator being the common ground when the vehicle is not running(which is what gives you the bulb test function when you have your key on but engine off)or the alternator or it's wiring is shorted to ground mimicking the bulb test. 11.7v is low for static battery voltage. This could be a symptom of an alternator issue or it could be a battery issue. Being that this popped up in the process of other repairs I would suggest checking all the areas you've been working in to see if you may have jarred something lose or broken a wire.

Have a look here as well as try searching "Christmas dash/lights".

Thank you so much for the ground info. That's going to come in handy in the future. I have my battery on a trickle since last night. I have an extra alt laying around. Once the rain stops(if it ever does). I'll put it in.
Don't want more headache besides the tranny issue. Ughh!
Figures crossed
Thanks
Keep on vanning