wiring harness nightmare

[79rustyk10]

Long story short, I took the entire wiring harness out of an 88 blazer, as part of the TBI swap. This is the entire dash harness and engine harness. I put it in my 79, I swapped the steering column in to get the tilt and newer style wipers along with it. The truck is not running yet as I still need a correct gas tank.

Now I put a battery in and try things out, and the first thing I noticed was the SES light will not light up at all. I started checking around and there is no power at the terminal at the alternator, and half of the fuse box is without power. The ecm a fuse has power but ecm b does not, Im guessing this explains the lack of a ses light. also none of the constant power terminals on the fuse box have power, nor any power to the headlight switch.

With key on engine not running there is no idiot lights on but when I turn key to start, (it does turn the engine over)the brake light comes on. I know with key on engine not running the SES light should be on.

I have no idea what else it could be, the only things I eliminated from the harness was the dome lights, maybe there is a fusible link somwhere that I misses, The one on the alternator has no power ahead of it, im guessing that ones still good.

Thanks.

The 88 blazer ran and drove before it was parted out by me.

 

[ryoken]

there should be 2 power supplies to the fuse block... 1 from the back of the alt, and one from the junction block by the booster, which is fed from the starter...

 

[blazin_blazer]

this is exactly why i think i'm carbing my new 87 454 tbi engine going in my 84 k10.

 

[79rustyk10]

I have constant power at the junction block.

just ran a jumper wire from the pos. terminal on the battery to the terminal on the back of the alternator, and now everything else seems to be how it should. I dont remember how it was in the blazer but I dont think having that wire is correct.

I understand the reasoning for going carbed, but it gets pretty fockin cold here in mn and the added driveability is always a plus.

 

[ryoken]

How else would you be charging the battery without that wire? the factory one is about 8g iirc...

 

[79rustyk10]

I dont remember that wire being there when I took it apart, but then again it was about a month ago when I pulled the blazer apart.