I am going with a stand alone harness for my swap and had some questions about the extra leads that come with it.

Here is a list of leads that come with the stand alone harness I am using that must be tied into the original harness on the vehicle or added. I have been trying to determine on my own which wires they go to on the stand alone harness. If someone could help with the ones I don’t have listed, please let me know.

● Lead for Vehicle Speed Output (Speedometer) WIRED TO ?

● Lead for Park / Neutral Signal Input WIRED TO ?

● Leadfor A/C RecognitionSignal Input (Accepts a power inputsignal for A/C) WIRED TO ?

● Lead for 12-Volt Switched Ignition Power WIRED TO F4-PINK AT C100

● Lead for Fuel Pump Positive Output (Powers fuel pump) WIRED TO ?

● Lead for Tachometer Signal Output WIRED TO D6-WHITE AT C100 (TACHOMETER)

● Lead for Brake Switch Signal Input WIRED TO ?

● Leads for Check Engine Light (Ignition Power and Trigger) WIRED TO ?

This harness has a Connector for Fuel Pump Relay (Includes Relay), a Four Position Fuse Block (Includes Fuses) and a Connector for Assembly Line Data Link (ALDL) so Im also working on a custom 90-92 C100 diagram using the stand alone harness that Pocket made to match this info below and where I have hopefully determined torun the wires to the Starter to/from.

I thought this thread would help me and everyone else oncethis was completed. I have gotten a lot of help from the board and would liketo assist in some way too!

 

That's 90-92 specific
Speedo wire to pin d (v6 and TPI), pin k (TBI) with buffer bypass
86-89 firebirds pin k (all engines) with buffer bypass

P/neutral c207 pin n

Ac request lt blu wire on the hvac box underhood

Ign can come from any pink wire from the c100/c207

Fuel pump c100 g4 89-92 cars. Varies on older cars

Tach is d6 for all 82-92. Early carb cars use a blk/wht wire instead of the universal wht

C100 e7 is the brake switch for 90-92. I recall some older cars running it through the c207

MIL is c207 pin c for all years

 

Thanks for your help! I picked up the rest of the wiring schematics today from the dealership to study as well.


On the C100, shouldn't E7 be for the brake switch, not C7?

So the Lead for the A/C Recognition Signal Input on the Stand Alone Harness is the same thing as the AC ON INPUT which originally went to ECM B8?

 

Typo, sorry

Ac request is on the hvac connector in the engine bay. I do not recall the original ECM terminal, or if it had one

 

wow thanks, this is great info, I been on the fence about doing the harness myself or just paying someone. Ill be watching this thread, if you could post some detailed pics as well, Im more of a visual learner, not big on text book style learning haha. Thanks again for the great and much needed info

 

I second that. I would love to see some detailed picks of one of pockets harness installs. I think a visual would really bring it home for me and a lot of others here.

 

What is the buffer bypass? Is that removing the buffer all together? I've got the schematic and see Pin K on my vehicle and see where it goes into the VSSB.

Also, other than the wire at C207 for the speedo and the ones you put an asterisk by above, are all the other wires at this connector removed or no longer used? I saw one that goes to the cruise and I'd like to keep some type of cruise setup also.

 

Anyone out there?

 

Buffer bypass is simple. Unplug the module, connect pins c&f

The rest of the pins should be self explanatory. Do you have the equipment related to the circuit? Do you plan on using the circuit?

 

Hey Pocket, I'm doing an LS swap as well and am confused about the buffer bypass. Why do pins C and F need to be connected together? Can't the wire from pin C from the buffer box just be connected straight to pin K(VSS signal 4000ppm speedo output from LS1 PCM) of the C220 connector on the LS1 harness?

 

Yes

The downside there is a single wire that runs outside the loom between two connectors not very close together. Troubleshooting years down the road becomes tricky

Jumping the pins and using the c207 pin keeps everything inside the loom along the factory paths

 

Oh alright, thanks for the clarification Pocket.

 

Do you wire these direct to the wire or at the back of the c100 connector?