pat12spe

I'm kinda stuck on where to go from here, hopefully one of you guys has a diagram that can help me out. I'm looking for a diagram of wiring for the VSS to buffer box to ecm/speedo/cruise control for an 87-89 firebird tpi as well as a 90-92 tbi if someone happens to have it. And if they are the same please let me know. Even if it's just sketched or drawn on computer, that would work, I'd just like to know where they are supposed to hook up.

srdynamics1

iTrader: (10)

www.autozone.com
They have it on their site somewhere. wealth of diagrams.
(I had to get to you before the search button police began pecking away at their keyboards)

dr1

for whatever reason i have an 87, 89 and 90 firebird factory service manual, so if you dont find it on autozone let me know and ill do my best to draw something

pat12spe

Yeah, I saw the diagrams on autozone's website but I don't think they are the same. Any chance you could just give me a drawing for the VSS and where it goes to the speed buffer and ecm and such? That's all I need. Thanks.

pat12spe

Here's the dilemma. I bought an 87 camaro wiring harness for a MAF setup and it doesn't have the VSS hookup on it. I want to transplant the VSS from my old tbi and I need to know where it hooks up on the camaro harness. I need to know about the speed buffer also. Thanks.

dr1

uhm.. finally got a chance to look at this and wish i had a scanner... i hope i offer some help with this (no its not a picture but its the best i can do)

from what this says there were 2 types for 87, a permanent magnet generator VSS or an optical type, which is in the speedometer itself.. cable driven one i guess

87 VSS optical type:
pnk/blk (buffer) --> pnk/blk - guages fuse
brn (buffer) --> brn - ecm & cruise control module
blk/wht (buffer) - ground


87 - magnet generator type
pnk/blk (buffer) --> yellow - vss
blk (buffer) --> ppl - vss
pnk/blk (buffer) --> pnk/blk - gages fuse
lt grn/blk (buffer) - instrument cluster
brn (buffer) --> brn - ecm
red (buffer) --> brn - cruise control module
blk/wht (buffer) - ground

90 tbi
pnk/blk - gages fuse
brn --> brn - ecm
tan - instrument cluster
red --> red - cruise control module
yel --> yel - vss
ppl --> ppl - vss
blk/wht - ground

sorry for being so late, and sorry if this is completely useless, if i had a scanout id give you an image but this is the best i got

pat12spe

That's exactly what i need, but you don't happen to have where exactly on the c100 panel, ecm, buffer box they connect to do you?

dr1

these schematics are too detailed for there own good so im gonna give it a shot here real quick

87 VSS optical type:
pnk/blk (buffer, 6 on C2) --> pnk/blk - guages fuse
brn (buffer, 4 on C2) --> brn - ecm (A10 on C1) & cruise control module
blk/wht (buffer, 5 on C2) - ground (5 on C2)


87 - magnet generator type
yel (buffer, A on C1) --> pnk/blk - vss (D4 on c100)
ppl (buffer, C on C1) --> blk - vss (E4 on c100)
pnk/blk (buffer, H on C2) --> pnk/blk - gages fuse
lt grn/blk (buffer, C on C2) - (14 on C1) instrument cluster
brn (buffer, F on C2) --> brn (A10 on C1) - ecm
red (buffer, E on C2) --> brn - cruise control module
blk/wht (buffer, A on C2) - ground

90 tbi
pnk/blk (H on C2) - gages fuse
brn (F on C2) --> brn (A10 on C1) - ecm
tan (C on C2) - (C14 on C1) instrument cluster
red (E on C2) --> red - cruise control module
yel --> yel (D4 on c100) - vss
ppl --> ppl (E4 on c100) - vss
blk/wht (A on C2) - ground


hope this helps any better, its getting scary looking

pat12spe

ok 90 tbi i see the vss goes to D4 and E4 on the C100.

But what about the 87 optical? I'm hoping it should be the same on that also. That would make my job so much easier.

dr1

the VSS and buffer are part of the speedometer on that system.. if thats the harness you have, i would imagine the wires for the other system would be there somewhere.. but perhaps not

pat12spe

Yes your right, my fault. I have the magnet generator type. I wasn't thinking straight. Looks like a 87 MAF GTA harness will swap directly with a 90 tbi. Thanks for the help!!

dr1

np glad i could be of help

drew_motohead

so...89 chevy k15 700r4. tbi, elec speedo, 5.7

on the tranny, drivers side, a 4 prong plug connects vertically into the tranny.
only 3 prongs are used
_____
|A-B|
|C-D|
-----
A) +12 input. pink/black wire from 10 amp ign source, through brake pedal interupt switch, then out on a light blue or light green wire to your vac switch, then to your tranny.
B) OUTPUT (green)- goes to ground when tranny is in 4th gear

C) ground (black)- requires ground to complete the lockup circuit.

D) Not used.

info from:V8S10.org :: View topic - ****700R4 WIRING!!**** All info for hooking up 700r4 click!!

question 1:
if you do some searching...or just go to here

you can see that by putting a switch on the green wire...you can control wether or not your trans will lock up in 4th. advantages...disadvantages...but this aint my prob. my prob is that im not getting 12v on the A wire, driving, parked and running, pressing the brakes...nothing. but, it says that wire goes through a brake switch and vac module...NEITHER I CAN FIND OR EVEN THINK I HAVE!!!! (previous owner was a little rough on the electrical...so im screwed.)

THE QUESTION-----> can i just find me a ignition power source and hook it right up to that A wire??? bypass all thos dang switches, mabye put a switch on it to....will this have neg consequences????
also, how can i find out that that B wire is grounding in 4th??? get a test light and hook it up to that and power and see if it lights?? or does this ground through the ecm or something? same goes for other wire.

QUESTION 2:

heres my crappy scematic:
under dash, on firewall, drivers side, a distribution block with more than a couple wire coming off
----a brown and a black wire exit off block, go down through the hole for the 4wd shifter along with a white(or yellow) wire that looks like its for the indicator light for 4wd.

all 3 wires go into a 3 prong connectorabove the tranny/tcase with A B C on connector
----A) brwn------------***********---brwn------THIS WIRE IS BROKE
----B) yel or white----*connector*---wht or yel
----C) black ----------***********---black

I DONT KNOW WHERE THAT WIRE GOES!!!IM THINKIN THATS MY POWER FOR THE a WIRE....ANYONE KNOW WHERE THIS GOES??

the remaining wires go into that 4 prong conn discussed on top...and then go to my next question...

QUESTION 3
there are 2 connectores mounted vertically on my front "axle" damn near dead center. ones a 2 prong the other is a 4...

WHAT ARE THESE THINGS???? manual says "thermal actuator" and "indicator switch" (IFS, rear abs,4wd) i ask cause the 4 prong connector above, the VSS on the t-case, are all tied together.

i am getting a code 24...no vss present

the reason im diving into this is i heard horror stories of what a malfunctioning VSS can do. im going to specifically test the vss tomarrow...testing AC current b/t the 2 wires as i drive. but, because that broke wire could be whats causing a vss code, PLUS not knowing if my tranny is performing perfectly (i.e not locking up, trying to lock up at wrong time, locking/unlocking, or it could even effect my shifts, my tranny shifts great, but i never had a truck like this, so have nothing to compare it to...ya know? dont wanna break my new gearbox!!! PLUS the wiring diag in serv manual says that a bad VSS could cause other systems to not work right (IAT sensor, O2 sensor, and timing i think) and my truck dont run perfect yet.