I very recently installed base c7 seats into my
02z and what a difference!! There is no going back to stock seats, even if I re-foam them w jute padding!

I did a lot forum reading on how to install these seats and how to wire them. There are many posts about installing these seats and each had valuable information in them, but for someone who hasn’t done something like this before, it was sometimes difficult to piece together how it all came together to create the wire harness. So with that, I wanted to pass on my learnings in a start-to-finish post focused on wiring in base c7 seats to a c5z.

There are a few ways to wire these: using spade connectors only, sourcing all oem clips, or buying a harness. I took an approach using both oem and non-oem components.

What you will need:

• Soldering gun
• Crimpers
• Wire strippers
• 3 Male spade connectors per seat (not sure of the sizes but pix below)
• 1 Female end from a c5 seat harness (can be found on Amazon but mine came from a salvage yard)
• 2 two-prong weather packs
• 1 four-prong weather pack
• 1 25ft roll of 14awg with 2 conductors in one insulated case (amazon)
• Heat shrink
• Electrical tape
• Box cutter (cut open the insulation around the 2-pronged wire)

What you’ll need (mostly)

Starting off

First step is to modify the c5 female adapter. Basically cut the pig tail from an oem seat harness and remove all wires from except the thick orange (power) and thick black (ground) wires

Next you will want to assemble the male end of the 4-prong weather pack using your wire strippers/crimpers and the male/female prongs included in the weather pack plug assembly.

This is the point in which you’ll jump power to the passenger seat. I used 14 gauge red (power), black (ground) for what would be the passenger side power source, and I used the oem c5 connector’s orange/black wires for the driver seat set up. To jump power from the driver side to passenger side, I soldered the red/orange power wires together and soldered the black wires together. After soldering, heat shrink was used for a clean finish.

Since the C5 power/ground wires were the same size as the 14 gauge wire I bought for this project, I used a cut-to-length scrap piece of insulation from the red/black wire spool I bought and used that to wrap around the c5 orange/black wires coming from c5 plug to the 4-prong weather pack. The way the insulation was molded, the orange/black wires fit nicely into grooves where the red/black wires once were. To ensure the insulation stayed on properly, I wrapped it in electrical tape.

The c5 to 4-prong weather pack portion of this wiring set up is now done.

Pictures below show the creation of the c5 harness to male end of the 4-prong weather pack

Starting to jump wires so the passenger seat is powered


Wires jumped, but need to remove unneeded wires from the c5 harness and clean things up


Wrapping remnant insulation around the c5 wires going to the 4-prong weather pack, and wrapping electrical tape around the insulation


C5 harness to 4-prong connector finished


Finishing the 4-prong weather pack

Next up is completing the female end of the 4-prong connector, first focusing on the driver seat. I used red wire for power and black for ground. The red wire matches to the orange power wire and black wire matches to black. These same red/black wires will lead to the male end of a 2 prong weather pack connector.

You’ll add a red/black wire to the female end of the 2-prong weather pack so the power/ground wires on the male half of the connector correctly align.


What the finalized 4-prong weather pack looks like.


The other end of these wires will have spade connectors crimped to them and heat shrink applied. I used a larger blue spade connector for the black ground wire. For the red power wire coming to the seat, you’ll need to first solder another red wire to its end. This enables you to jump the power into 2 points within the c7 seat harness. The end of the red wire that was soldered is then crimped into a yellow spade connector with heat shrink applied (a yellow spade connector seemed to fit tighter into the c7 seat harness). The additional red wire acting as a jumper in the seat harness will have a small, blue spade connector crimped to it and heat shrink applied. I had to dremel this small, blue spade connector it so that it was narrower. Without doing this, the connector from my kit was too wide to fit into the c7 harness.


Driver side, 4-to-2 pronged weather pack connection


Three spade connectors that go from the female end of the 2-pronged weather pack to the c7 seat harness


Driver seat connection, view 1


Driver seat connection, zoomed in. Note where the wire is zip tied to the seat so the spade connectors aren’t disturbed

These steps are repeated for the other red/black wires in the 4-prong weather pack that will be the power source for the passenger seat; however, the passenger seat connection to the c7 harness is slightly different than the driver side. (I forgot to snap a picture) Basically- the top wire from the driver seat picture is not inserted into the 3rd contact from the right, but rather the top, right-most connection when it comes to the passenger seat connection)


What the whole harness looks like just prior to installation (only showing one connector going to the c7 harness since both driver and passenger sides are identical)

Routing the wires in the C5

To route the power/ground wire from the female end of the 4-prong weather pack connector, I ran it up behind the driver seat and over the back of the center console. From there, I ran down the passenger side of the console to the floor- where I laid the wire along the floor to the opening in the carpet meant for the front inner passenger seat mounting bolt.


Driver side with wire installed

Passenger side with wire installed

Post-installation checks

Once installing the harness in the car, I tested the seats to confirm functionality before installing them in the car. The last step before installing the and powering up the seats would be to zip-tie the wire coming from the c7 harness to some point in the c7 seat frame so that the spade connectors are not pulled out of the harness after final installation.

This wraps up the how-to for a wire harness creation. There are already comprehensive posts on how to modify the c7 seat to fit into a c5, so I am not covering that portion of the install. You may recognize some of this work from other posts, which were big sources of inspiration.

I do want to thank @jdmvette and @C6-LS2-MN6 for their time answering my questions while I was figuring out how to do this.

I hope this post is of help to anyone looking to make a c5-to- c7 wire harness! It seemed a bit daunting when I first started, but it ended up being much simpler once I started work on it.

 

^ excellent job!

 

Great writing, I love when guys like you take time to post their work just to help others forum members. I have pristine C7 seats coming from a 2018 1LT that I want to install during the winter and I have not decided wich route I’ll take for the wiring but I will definitely consider your way. As for the installation did you have to modify the seats looks like it’s a tight fit. Thank you

 

Good luck with your install! I love those red seats. If my car wasn’t torch red, I would have looked for a red set.

I really wanted to use all oem connectors but I had a tough time finding the male portion of the c7 connector without having to buy the entire wire harness, which was more than I wanted to spend. If I come across the connectors in the future, say at Carlisle, I’ll swap them in for a cleaner look.

As for seat mods, I am pretty tall so I had to cut off half the c7 seat switch cover so I could adjust the seat far enough from the steering wheel. Surprisingly, head room is still pretty decent.

 

thanks for taking the time for this -- we have a bunch of random threads on this, but always nice to have a step-by-step for the newbies!
Do you have telescoping steering in your car?

 

power telescoping steering have never been available in Z06

 

yup, my bad, you are correct :-)

 

I always offer the use of Tesa tape as a wire wrap. It is a soft and silent fabric tape which does not degrade to a greasy mess over time or with heat. I've become a bit ocd with it and removed all of the oem brown glue/foam junk from my dash harnesses and replaced with this.

Great and detailed write up here by the way. Thanks!

 

Thanks Tusc! I also wondered what that fabric tape was called. Now that I know, I’ll also be removing that messy foam tape the next time I need to remove any of the panels. I’ve been cleaning it up as best as I can but is still not clean enough for my liking

 

Same company also offers it in a high heat version for under hood use. Much firmer material though.

 

Hi OldMan, does the connector from the C5 seat have to come from a Z06 or any C5 I can find. Thanks

 

I am nearly certain the main power connector is the same across models. My adapter came from a used salvage harness that had other power connectors my oem Z06 seat harness doesn't have. It was just matter of cutting off the wires not needed in a Z set up, or popping out those unneeded plugs within the connector

 

Great write up - thanks for posting this as it will help anyone looking to do a seat upgrade on their C5.

 

Thanks @Vetteman Jack!

 

May I ask where did you find the 4 pin connector I can’t find anything with a reasonable price. Thanks

 

Fastronix Weather Pack Connector Kit (4-Pin) https://a.co/d/fvVwDnG

Exqutoo 6Pack 4-Pin Waterproof DT Connector Male and Female Wire Connectors with 16AWG 105℃ 600V Wires and Heat Shrink Tubes, Applicable for Automotive Electrical Connections https://a.co/d/c81alPw

 

I ended up going with the connector. So far, so good.

 

hello, was wondering if the seat switches just pull off or if they are attached some other way?

thanks

Len

 

Hi Len! The weatherproof connectors clip together so they won’t pull apart without it being intentional. The wires with a male spade plugs to the c7 seat connector can pull out if they catch on something but I zip-tied them to the seat (giving them some slack at the point where they plug into the c7 connector. They are quite stable with this set up.

Zoomed in on where I zip-tied the harness to the seat

 

Hi- I realize the thread is old but this is the best write up out there.

Curious if I already have power on the passenger side would I just need a 2 pin adaptor?