My harness was cut by the previous owner, and the only local harness available was from an automatic car.

So I was planning on splicing the reverse lights using the TCC wires.

Does anyone have an under-dash schematic of the reverse light wires? I imagine they go to that small white connector on the passenger side, and not the C100 connector, correct?

-- Joe

 

I did the same thing when I replaced my slush-o-matic with a T5. I simply took the dark blue and light green from the shifter switch connector and ran them through the tunnel straight to the driver side connector on the T5 case.

Hope this helps.
Lou

 

Well the car is a manual car, so I don't have any wires to where the automatic shifter would be.

I suspect, on a manual harness, the reverse light switch goes to the third connector next to the ECM. But I'm not 100% sure.

-- Joe

 

Sorry, I misunderstood your post. I thought you were going to use an automatic harness.

Yes, your manual transmission harness has the dark blue and light green wires go through the C100 and then down the tunnel to the driver side of the transmission.
Where under the dash, is unknown to me. I would assume just the shortest path in the harness. The dark blue wire comes off the turn signal flasher that's clipped to the fuse box. The light green wire travels rearwards under the door sill and carpet next to the driver seat.

 

Do you KNOW the year of the replacement harness ??

Sounds like your replacing the DASH harness in an 88 Firebird Stick, and that the swap dash harness is from an auto. If it's also from an 88 Firebird I'd GUESS that the reverse light wiring exits the interior in the same place. ( Isn't the Firebird Dash wiring harness made for BOTH auto and stick cars ?? )

I've seen ThirdGens reverse lights run thru C100 and thru C207 on before. When it comes to wiring I find it's ALWAYS important to know exactly what year the wiring is from because circuits are very dependant on year and tranny type.

 

No, I replaced the engine harness, with one from an '89 firebird automatic. The dead giveaway is '89 is the only year that omits the cold start injector.

On an automatic, the wires are part of the dash wiring and go to the shifter for reverse, park/neutral, and 4th gear switch. On a manual car, the reverse light wires come out of the engine harness, but I'm not sure if they go to the C100 connector to merge with the rest of the lighting circuits, or if they come in through the small connector.

-- Joe

 

I don't have an 89 Shop manual to be sure,and the closest manual I've got is for an 88 Camaro.... BigBadLou has it right;

Auto:
Dark Blue runs from the NSS to the turn flasher, then onto the Turn/Back-up fuse.

Lt Green runs from the NSS down the body harness and to the taillight harness.

Stick: Both wires run thru C100. Blue @ B5 and Green @ C4

You can tap into your manual harness at the dash side of C100 and run them anywhere you want to the tranny. ( thru a hole in the firewall, under the center console and dropped thru the shifter hole ect,....). You could also remove a couple (long !) wires from the original hacked engine harness and re-pin them into the replacement harness @ C100 B5 and C4 too.

Good Luck !

 

You guys are awesome! Thanks, now I have a plan.

-- Joe

 

I know, old thread has new life. Just wanted to say thanks for posting this info. I'm almost done with my engine swap and couldn't find where these went. You saved the day!