oneslowz28

Lt1 into 3rd Gen swap wiring

By Oneslowz28

I do not hold any liability to damage to any property. This write up is just a reference guide to help you wire up your car. You should always double check the wiring schematics in the factory service manuals.

If you follow these instructions your car will start up on the first try. This write up was made using the 3rd Gen C100 bulkhead connector I highly suggest using yours or going to a junkyard and getting another one. All you will need is the side that is not part of the headlight harness you can leave that on your car. This write up was made using A lt1 from a 94 with a 94 wiring harness and a 94 ECU, and under hood relay/ fuse block. . Other years may be different but this will work with a 95.

First we will take care of the 3rd Gen C100 Bulk head wiring. There are only a few wires that have to be spliced here you can delete the rest if you would like. Pin outs with N/a or Not used can be deleted. Wires must be soldered not crimped with a butt connector. Any wires that are going to be in close proximity to a high heat area should be loomed and heat shielded.

3rd Gen C100 bulkhead wiring.

3rd Gen C100 Bulk head / Lt1 harness


A4 Red Power Dist. / Wire to constant 12 v

A5 N/A

A6 N/A

A7 Pink/black / Not used

B4 purple / Wire to starter solenoid

B5 N/A

B6 N/A

B7 N/A

C4 Tan/White Not Used

C5 Purple wiper/ washer

C6 Dk Green wiper /washer

C7 Pink wiper/ washer

D4 Yellow Vss not used.

D5 Gray Wiper /Washer

D6 Black/white Tach / Wire to pin d (white) on C230 Lt1 harness

E4 Purple Not used

E5 Tan Oil pressure signal / Wire to pin B (Tan) on C220 lt1 harness

E6 N/a

E7 N/a

F4 Pink/black Not used,

F5 Dk Green coolant temp signal / Wire to pin K (Dk green) on C220 lt1 harness

F6 N/A

F7 N/A

F8 Brown charging system / Wire to pin A (red) on C220 lt1 harness

G4 N/A

G5 Red Power dist. / Wire to constant 12v

G6 N/A

G7 N/A

G8 N/A



Lt1 harness connectors.

Some of the wires on these connectors have been wired previously when you wired the 3rd Gen C100 bulk head. Some of the wires are not used and you can delete them. This write up does not include the VATT'S (pass key II) wiring as most people have it tuned out.

C210 Black 4 pin connector

------
[A] [B] [C] [D]

A purple Wire to starter solenoid
B Black/white Ground to body
C Orange Wire to Constant 12 volt Fused
D Gray Not used


C220 White 10 Pin connector

------
[K] [J] [H] [G] [F]
[A] [B] [C] [D] [E]


A Red Wire to F8 (brown) on 3rd Gen C100 bulkhead connector
B Tan Wire to E5 (tan) on 3rd Gen C100 bulkhead connector
C Brown This is the low oil light feed. Wire to low oil light on dash if you have one.
D Orange/Black Not used
E Tan/Black Not used
F Tan Wire to pin M (tan) on ALDL port
G Dk Green/White Wire to pin H (pink/black) on yellow VSS box under 3rd Gen dash
H Dk Blue/White Not used
J Dk Green/White Trigger wire to turn on fuel pump relay. Wire to Fuel pump Relay
K dk Green Wire to F5 (Dk Green) on 3rd Gen C100 bulkhead connector


C230 Blue 10 pin connector

------
[K] [J] [H] [G] [F]
[A] [B] [C] [D] [E]


A Light Blue Not used
B Brown/White Wire to check engine light on instrument cluster
C White/Black Wire to pin B (black/white) on ALDL port.
D White Wire to D6 (Black/White) on 3rd Gen C100 Bulkhead
E Dk Blue Not used
F Dk Green/White Splice into A/C clutch switch
G Pink Needs to receive Cranking 12 volts
H Light Blue/Black Not used

J Orange/Black Ground to body
K Tan/Black To transmission for converter lock up


ALDL Wiring.

Use a ALDL port from a Obd1 4th gen.Some of these wires have been wired already just skip them and wire the rest.

B WHT/BLK Wire to pin C (black/white) on C230 lt1 harness
A BLK ground to body
M TAN Wire to pin F (tan) on C220 lt1 harness
G BLK/WHT Not used

================================================== ================================================== ================================================== ================================================== ================================

After several request for the 3rd gen c100 bulkhead wiring descriptions I have decided to post the scans .There are 2 scans for the 3rd gen c100 connector. Just click on the thumbnail and it will enlarge.

3rd gen c100 bulk head out side half wiring descriptions scan 1.

3rd gen c100 bulk head out side half wiring descriptions scan 2.

I have also decided to include the pinouts for the lt1 harness (its a 95 lt1 harness but should work for a 94 too.) The link to the 95 lt1 harness will take you to the image on Shoebox's website. . Much thanks to him for creating this wonderful site. http://shbox.com

95 lt1 harness. http://shbox.com/1/harness.htm

lt1 harness pinouts
C100
[A] {B} {C} {D} {E}
{K} {J} {H} {G} {F}
------------
a pink power feed from injector fuse #9
b Dk green/white A/c Compressor relay control
c Dk green a/c compressor clutch solenoid feed
d light blue traction control active
e brown air pump control
f brown Power feed from fans/ actuators use #6
g pink Power feed from injector fuse # 11
H Dk blue secondary coolent fan relay control

J dk green primary coolent fan relay control
K pink power feed from injector fuse 10




C210
--------
[A] {B} {C} {D}
A purple Theft Deterrent relay to starter Solenoid feed
B Blk/wht Ground feed to fuel pump relay
C Orange Power feed to pcm bat fuse to pcm
D Grey Feed from fuel pump and fuel pump relay to prime connector
C220
------
{K] [J} {H} {G} {F}
{A] [B} {C} {D] [E]
A Red Generator feed to instrument cluster
B Tan Oil pressure feed to instrument cluster
C Brown Oil level feed to instrument cluster
D Orange/Black Spark Retard Request
E Tan/Black Throttle Position Sensor Signal (EBTCM)
F Tan Serial data signal
G Dk Green/White Vehicle speed signal
H Dk Blue/White (Automatic) Performance switch signal
J Dk Green/White Fuel pump relay control
K dk Green Coolant temperature feed to instrument cluster


C230
------
{K] [J} {H} {G} {F}
{A] [B} {C} {D] [E]


A Lt Blue Performance switch indicator control
B Brown/White Service engine soon indicator feed
C White/Black Diagnostic request signal
D White Tachometer signal to instrument cluster
E Dk Blue Theft deterrent-fuel enable feed
F Dk Green/White A/c request signal
G Pink Power feed from PCM ignition Fuse #5
H Lt Blue/Black TCC switched power feed

J Orange/Black Park/neutral feed from transmission
K Tan/Black Torque converter clutch control

ALDL port

Pin B (WHT/BLK) is your field service enable (D20 @ the PCM)

Pin A (BLK) is your ground

Pin M (TAN) is your serial data line (D30 @ the PCM)

Pin G (BLK/WHT) goes to the keyless entry (this is not needed)




If anyone notices anything i missed or is just wrong please post in here and i will change it.

oneslowz28

Saved for future write up content.

oneslowz28

thanks to jason for the stick!

Rage

Where exactly is the C100 connector on the car?

Dave89IROC

next the brake booster IIRC

oneslowz28

its to the right of the brake booster on the 3rd gen. you have to remove it by removing a 10 mm bolt iirc.

WS Sick

Are all thirdgens C100 connector pretty consistant?

oneslowz28

they varry in wire colors from v6-v8 and tpi tbi ect. but with the diagrams i have that i can email you you should be able to make. sense of it all.

WS Sick

I would really appreciate that. prpeterman@ptci.com

oneslowz28

I added to the write up the images are posted there. If you need anything else pm me.

WS Sick

Thanks , very nice.

oneslowz28

no problem. if you need anything else just post in here or shoot me a pm

ryan77

oneslowz28, I p.m'd you about a question on wiring

oneslowz28

shot you a pm back

jakesz28

I don't know if you can help me or not but I'm about to put a LT1 in my 91 3/4 ton truck (4x4). I'm wondering how to hook up the 700r4 to the lt1 harness? Is it possible to use the LT1 pcm to control the lock up torque convertor?

In this write up is it controlling the 700r4 or was this mainlyfor a manual car?

Thanks for any help you can offer