Not a green light comes on like normally... a yellow one comes oh

It's normal. It's part of the instrument cluster module doing what's called a "bulb check" on initial start up, and it should go off in under ten seconds, since it does, there is no problem

Your description, I take it, is a problem with the wiring harness going from the driver's compartment to the rear lights. If that is the case, the normal color code for GM is brown for tail lights, dark green for the right stop & turn, yellow for the left stop & turn and light green for the backup lights. Any black wires should be grounded. The white wire in the trailer harness is for a ground when used on a trailer. It sounds like you have the green and yellow T&S wires shorted together somewhere! Some of the later vehicles use separate stop and turn bulbs... these would have a separate wire for the stop lights only, but I don't think your truck is new enough for that. Good luck!

Check to see that your battery is secured. See if you can wiggle it. Make sure all battery terminal connections are tight, and all ground wires.

I would prefer if you forwarded a clear picture of these lights or symbols. The only green light I can think of is the one in the top center. That green light shows that your gear selector is in Park and moves as you select a different gear position. I think the yellow and Red light that you speak of is within the top area of the RPM gauge. The Red light should have an "!" symbol and is indicating a warning. The alarm is a back up to also alert you of an issue. This could represent your tires or engine. You should send it in for diagnostics asap. The Yellow Light I am not sure of. I need to know what it looks like. If it looks like a car with wavy lines. This light represents your traction control. If your car contains the owners manual it is a great idea to familiarize yourself with it. There is a lot of good information inside.

Power light indicators on flashing red as warning that battery is almost depleted of functionality. ascertain that devices with extension cables deriving power from elsewhere are plugged in to reattain power to acheive regular functionality. For example, devices with red light indication as power warning would also flash yellow or green when in full power charge from another source. refer with devices user guide or manual for refering, diagnostics.

Cool

Are your hazards lights on? I don't know your car but The triangle most of the time is hazards lights. Now when you turn your key on all the light should come on then go off, If on stays on in some cases it could be just a bulb. To check your Bulbs use you turn singles / blinkers. You can get them on by turning key to on with out starting car. Then turn on our left by pushing switch down first. Check driver side front & rear. Then check passenger side by switching to the right switch up. Good luck

It sounds like your battery is bad.

If both yellow and green LEDs come on, this indicates
a deeply discharged or defective battery pack.
Allow the battery pack to remain in the charger for 15
to 30 minutes. When the battery pack reaches normal
voltage range, the red LED should come on. If the
red LED does not come on after 30 minutes, this may
indicate a defective battery pack and should be
replaced.
n After normal usage, a minimum of 1 hour of charging time
is required to fully recharge battery pack.

Cavity
1 20 amp yellow hazard flashers
2 10 amp red heated mirrors
3 20 amp yellow body lights
4 not used
5 20 amp yellow windshield wipers
6 20 amp yellow turn signal lights
7 10 amp red radio
8 not used
9 7.5 amp violet illumination lights
10 2 amp pink left tail lights
11 2 amp right tail lights
12 not used
13 20 amp yellow rear window wiper/washer
14 2 amp pink speed control
15 10 amp red gauges, warning lights
16 not used
17 10 amp red left low beam headlight
18 10 amp red right low beam headlight
19 20 amp yellow stop lights
20 20 amp yellow rear a/c heat
21 20 amp yellow fog lights
22 20 amp yellow park lights
23 20 amp yellow battery
24 20 amp yellow back up lights
25 circuit breaker power windows,power vent windows
26 30 amp lt. green a/c heater blower motor
27 circuit breaker power door locks
28 not used

this is the normal condition> only when green led is off and warning temp led(yellow) is on something is wrong!!