I have been working on a '76 LeMans with a TPI 5.7L from an 88 TA.
Everything is hooked up, ignition comes on, starter engages, but at no point will the SES light come on. I have wired the ALDL and can't get it to come on unless I put power to it via the ALDL, so I know the light works.
The ECM pin-outs all have power where they should. I have tried two different ECMs and niether pulls up the light.
I tried running a couple of ALDL programs and they give me nothing back.
The paperclip method doesn't work, either.
I am just not sure what else to do.

Any suggestions?

 

I can help you out. I have done several of these conversions, in fact I just finished a TPI install into a '42 Coupe. Please tell me EXACTLY how you are trying to power it up. Does it do a bulb check? Is the bulb good? Can you jump it and get flash codes? There is another harness to the PCM (besides the engine harness) do you have that one? Does the car run or just crank? Spark? Fuel? Injector pulse? Give me AS MUCH INFO as you can and I can walk you riight through it.

 

Okay, I do have a harness to the PCM.
It is tied to an aftermarket fuse block.
I have hot constant to ECM.
I have hot in ignition ON.
When it is in the ON position, ECM harness is hot in several pin-outs.
So far, it all matches info I got from ChevyThunder for the wiring.
The SES is a 12V light I set up in the dash. It has the extra wire to the ALDL so if I put a hot 12V on that terminal, it lights up.
But when ignition is on, no SES light.
Jump does not give me any codes or light at all.

Engine cranked before hooking up the module, and still does.
I may have a fuel pump issue, but right now, I just wanted to know the ECM is okay.

 

Ok well, the SES is actually activated by GROUND through the PCM. There should be two wires going to you light from the second small harness (16 pin I/P harness) I asked you about. One side of the bulb should be hooked to the BROWN/WHITE wire. That is you "SES CONTROL". That is where you get your ground thus illuminating you bulb when needed. The other side should be hooked to PINK/BLACK wire which should be hot (powered) in the "ON","RUN" and "START" settings. You must also make sure you have a good ground on all the BLACK/WHITE wires off the main PCM harness. If you dont have good grounds, the light will noe illuminate. Also off the PCM 24 pin connector make sure you have the power on the PINK/BLACK (pin A6) wire as I mentioned earlier and also constant power (key off, on, start and run) on the ORANGE (pin B1) wire. If missing on PINK/BLACK thats supposed to get power from the 16 pin I/P harness so check that. If you have all that then it SHOULD light up. If not check all fuses, fuseable links etc. If all good, PCM bad. I know it is very confusing but its tough to explain from memory via a forum. Just take a deep breath, check ALL your powers grounds. Make sure the constants are constant and switched are switched. Makes sure grounds are good and ses is hooked up correctly. Keep in the cack of your head powers are bigger gauge PINK, PINK/BLACK, and ORANGE wires and grounds are almost all BLACK/WHITE and TAN. Where are you located? if you want to send me a private e-mail I can give you my number and maybe walk you through it. Good luck.

 

That was it! I had the SES grounded instead of running through the fuseblock. Thanks a lot!!

 

GREAT! Glad to help! You will love this setup in this car. Like I said I have done ALOT of conversions because they work out great! Please let me know what you think when its all done. P.s If you need anymore help do not hesitate to ask.