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That's a tough job. I don't have much advice to offer beyond double/triple checking the pinouts one-by-one as you go and again when you are finished. Most of the connections are point-to-point and easy to follow, but some of the ground and power junctions are located in odd places that are physically very different from how they're shown in a wiring diagram. Depending on how much you are changing things this can be a pretty simple job. I recommend doing it with the harness somewhat installed/routed on the engine so you can see where you want to reduce/change lengths or routing. On mine I completely depinned the ECM connectors and worked one sensor/group at a time because I had specific routing in mind. If you can live with the OE wire routings then I would only depin the ones needing extension/shortening/removing.
This to me is the most stressful part of the whole swap since electrical is not my thing. This is why I am trying to follow the info on LT1swap religiously! De-pinning per his info and fishing the connectors and wire out is not bad.. tedious, but not bad. Similar to what you said though I will be putting the harness back on engine one more time before I loom it all up to confirm locations and lengths and where to run fan wires.. I am actually looking forward to that part.. its just these questionable wires I don't want to rush through!
I feel ya. It can be very stressful especially given all the weird connectors that can be different year-to-year and application-to-application. Sorry I'm not much help but I thought I'd level some moral support - it's fundamentally very simple, just a lot of very simple connections that taken together can seem complicated. I think your approach is very good. Being a little afraid can help keep you focused and more careful.p
I love your car by the way. The green with side trim and vinyl top is awesome.
I feel ya. It can be very stressful especially given all the weird connectors that can be different year-to-year and application-to-application. Sorry I'm not much help but I thought I'd level some moral support - it's fundamentally very simple, just a lot of very simple connections that taken together can seem complicated. I think your approach is very good. Being a little afraid can help keep you focused and more careful.p
I love your car by the way. The green with side trim and vinyl top is awesome.
Thank you! I didn't really like vinyl tops but our cars pull it off
You can cut C100. Don't get hung up on the OEM "C" connectors, as you should use your own fuse/relay center like this one anyway. Trace wires back to the PCM, and remember that pink is ignition and orange is battery positive. Label everything to keep as you depin it.
I've built my harness both ways, and found that it's easier for me to start at each sensor/injector/coil and work back to the ECM individually.
You can cut C100. Don't get hung up on the OEM "C" connectors, as you should use your own fuse/relay center like this one anyway. Trace wires back to the PCM, and remember that pink is ignition and orange is battery positive. Label everything to keep as you depin it.
I've built my harness both ways, and found that it's easier for me to start at each sensor/injector/coil and work back to the ECM individually.
Here is the C100 plug and what I'm getting hung up on.. maybe you can help since you ran the 4l80e at the beginning..
A - No cruise - DELETE
B - Steering - DELETE
C - Off/ run/ crank ? Where would this connect if needed?
D - VSS - Where would this connect if needed. KEEP (Possible electronic speedo later?)
E - TCC Brake control? Where would this connect if needed? Is this not needed for auto trans?
F - Damping Lift? Delete?
G - MIL - KEEP
H - ECM/ PCM - KEEP
J - Oil Pressure Sensor - KEEP
K - Engine Speed Signal (Tach) -KEEP
L - Steering/ Cruise - DELETE
M - Class 2 serial - Delete?
N - Ign 3 Voltage - Delete?
P - Door control - DELETE
R - AT **** lock? Where would this connect if needed? Is this not needed for auto trans?
S - Cruise - DELETE
I feel comfortable about all the other wiring, its just this plug that's tripping me up. I want to keep items that could possibly connect to digital gauges later and not be too bare bones.
Here is a pic of the new headers. I did a test fit to check the length of my O2 wiring.
Here is the new transmission MLPS that has the two plugs that I needed.
And here is where I got with my wiring:
I have just a few wires left. I have spent a LOT of time trying to find a clear answer to my remaining wires and there have been lots of questions asked about them but not a lot of answers.
These are the wires and what I am thinking.. hopefully someone can chime in:
E2 (from C2 connector) - This was a pink wire that came out of harness from the process of thinning out per lt1swap.com. It is "Off/Run/Crank voltage (transmission, pcm solenoids). But I know power needs to go to trans.. F2 is also for the exact same thing and is still hooked up. So am I covered not using the E2? (both the same 1020 circuit).
Pin 33 - Blue connector - TCC brake switch - This looks to be the one that needs the switch on the brake pedal for torque converter - using a brake switch part number of DR497 which hookemdevils22 noted almost ten years ago now! Is this correct? Anyone have a diagram for the 4 wires on the switch?
F3 (from C2 connector) - AT/ lock out control - Only info I found was related to manual trans for reverse lock out. On wiring description it also notes automatics. I am guessing I can ignore and not use?
F11 (from C2 connector) Nuetrial safety switch - I am guessing I can ignore and not use?
F10 (from C2 connector) - Starter relay - ignore since large started power wire goes to ignition?
E3 (from C2 connector) - Park Nuetral position switch - I am guessing I can ignore and not use?
I have just a few wires left. I have spent a LOT of time trying to find a clear answer to my remaining wires and there have been lots of questions asked about them but not a lot of answers.
These are the wires and what I am thinking.. hopefully someone can chime in:
E2 (from C2 connector) - This was a pink wire that came out of harness from the process of thinning out per lt1swap.com. It is "Off/Run/Crank voltage (transmission, pcm solenoids). But I know power needs to go to trans.. F2 is also for the exact same thing and is still hooked up. So am I covered not using the E2? (both the same 1020 circuit).You can get rid of the E2 wire, you just need the F2 to power the transmission.
Pin 33 - Blue connector - TCC brake switch - This looks to be the one that needs the switch on the brake pedal for torque converter - using a brake switch part number of DR497 which hookemdevils22 noted almost ten years ago now! Is this correct? Anyone have a diagram for the 4 wires on the switch? The 2 sets of contacts closest to the plunger part is where your factory brake light wires (orange and white) will hook up. The second set of terminals will need an ignition power, fused of course, on one terminal and the wire on pin 33 on the other.
F3 (from C2 connector) - AT/ lock out control - Only info I found was related to manual trans for reverse lock out. On wiring description it also notes automatics. I am guessing I can ignore and not use?This is for the shift interlock, you wont need it.
F11 (from C2 connector) Neutral safety switch - I am guessing I can ignore and not use? Unless you're going to use the range sensor for your neutral safety switch, which requires a starter relay, then you don't need this.
F10 (from C2 connector) - Starter relay - ignore since large started power wire goes to ignition? Same goes , as for F11, you shouldn't need it unless you want to run a starter relay.
E3 (from C2 connector) - Park Neutral position switch - I am guessing I can ignore and not use?You don't need this one either.
using a brake switch part number of DR497 which hookemdevils22 noted almost ten years ago
has it... has it been that long?
we're lucky to have ls1nova71 with us. the reason I said you can just cut C2 is because it helps to focus on the ECM and loads (sensors, injectors, coils, etc.), rather than the connectors.
we're lucky to have ls1nova71 with us. the reason I said you can just cut C2 is because it helps to focus on the ECM and loads (sensors, injectors, coils, etc.), rather than the connectors.
yeah, I think the post I found was around 2009.. crazy.. doesn't sound that long ago.. but.. ugh.. getting old. Now you guys are considered pioneers haha!
Tomorrow I'm going to pull the motor! So to get ready I pulled the front seat out so I could get under dash easier for when I start wiring. Decided to inspect floors fully and found both front floor pans need work.. oh well. Then I checked the back seat for the build sheet and found out today is my cars birthday!!
03-29-2018, 11:56 AM
We need to submit your and Joe's threads to the national archives. 
