Looking for info on the wires in the ALDL connector and SES light. I'm thinking mine has the wires in the wrong locations or maybe just backwards.

I have no SES light function at all. When I jump the A and B terminals together to put the system in diagnostic mode my electric fan kicks on but no SES light... LOL

What wire colors are supposed to be in the A and B port n the ALDL connector? I found a pic somebody posted that looks like the "A" port has a Black wire w white stripe, and the "B" port has a White wire w black stripe.

My Black w/white stripe wire is in the "F" port, and the White w/black stripe is in the "E" port. (Seems backwards or flipped according to the pic I found)

SES light questions; I have Brown w/white stripe wire labeled as SES light. It is taped up with a pin wire. This pink wire is hot when the switch is on.
Do these both hook to the SES light, (+ on one side - on the other), Or does the brown w/white stipe wire hook to the light and the other pole hook to a ground?

Last one, will a LED light work for a SES light? Or does it need a "normal" bulb? (I have a LED now)

It's an ebay wiring harness from quite a few years back, and I can't remember the seller, so I have no way to ask him questions... .

A led will work with a 1k resister in series you need to make sure the long leg (anode) is the positive side and the short side goes towards the ecm (cathode), The check engine light has power on one side and the ecm controls the ground side through a brown/white wire on pin E7 on your 1227730 ecm. Sounds like the aldl is wired correctly b is a ground and a is a blk/white wire that goes to E12 of the ecm.

I have the same problem, I stick the clip in and my fans turn on... no SES light at all.

Does the bulb actually work?
Should light up with the key on and go off when engine starts

The fact the fans are running shows the ECM is correctly in the diagnostic mode

Yep, I read right over that when I was reading about the codes. LOL

I changed lights, (I have a stand alone tpi system), in mine and it lit right up. I didn't like the new light so I swapped back to the one I had before, (still not sure if it's a led or not), and it lights up now too. (Now I just have to get it to shut off... LOL)