AnotherS197GT
Serial Valve Dropper
I was tired of constantly tapping my TCS button to shut it off every time that I got in the car. When I forgot, I'd get that familiar shudder and feeling of the TCS kick on when I floored it. After lots of frustration, I found a few write ups on how to wire a relay to automatically shut off the TCS. I had some trouble with it, so I though I'd make a guide for dummies.
This mod is useful for all 05-09 GT owners, especially people with F/I, as the TCS pulls fuel instead of spark. Even though TCS can be disabled via tune, it leaves an annoying light on your dash and its not able to be turned back on via the button. Wiring a relay in allows you to retain use of the button, as if there was no relay.
What I used:
3 colors of 18 GA wire
Package of crimp on female connectors
package of wire taps
regular relay
add a fuse
10A fuse
zip ties
3M two sided tape
shrink wrap
You will need to disassemble the center console. Remove the upper console piece by unscrewing the 2 screws under the center console lid. Lift up on that and remove it from the car, or just position it out of your way. You will then have to remove the two side trim pieces on either side of the radio by pulling them straight towards you. Once you have those removed, you have to unscrew the 7mm (6) screws that hold the finish piece on over the radio. You can either remove the whole panel by disconnecting the 3 plugs on the top and the 2 on the bottom, or just try to work around it.
I first tried to tap into a source that was hot only on start to avoid using an add a fuse. I was unsuccessful, so I tried using an add a fuse. I tapped into a hot on start fuse with the add a fuse. Fuse 20 in the smart junction box. Its in the passenger footwell. Put in your add a fuse and connect one color of wire to the end of the add a fuse. I chose to use red.
Next I ran my hot wire along the firewall to the center console. I attached it to another harness with zip ties.
Connect your red wire to the relay on terminal 85.
Next you will need to ground the relay. You'll want to splice two pieces of black wire together so that you end up with two places to add female connectors and one longer length of wire to run to the metal center console bracing to ground the circuit. Slide a piece of shrink wrap over each piece of bare wire, crimp on a female connector, slide the shrink wrap over it, and shrink it! Plug these female connectors on to terminals 86 and 87 of your relay. Unfortunately I didn't get a picture of my finished product, but here is what it should look like before the female connectors and shrink wrapping. The longer "tail" is what will be bolted to the center console. The other two ends get connectors and shrink wrap
Now take your last color of wire and one of your wire taps. Locate the TCS wire. You'll be looking for YEL/PNK or WHT/PINK. Its pin #7. Now you will want to place the TCS wire and your last color of wire in the wire tap and press the metal guillotine down with a pair of pliers. Snap it shut and run your wire down to the relay.
Once you have enough wire to reach the relay, snip it, strip it, add a female connector and shrink wrap it. You'll plug this into terminal 30 on the relay. Once you have all your wires connected, you will ground the relay and you can mount it right by the ground. I used the bolt in this picture behind the wiring.
All I did was take the bare end of the black tail and loop it under the bolt. You could buy a crimp on loop at radio shack if you want. I then took a small piece of 3M tape and taped it to the metal support of the instrument panel. Before mounting, make sure the relay is working!
The relay will flip the switch when you try to start the car. All you have to do is turn the key to run. If the relay is working, your TCS light on the TCS button will light up. If its not working, the light will stay off. As you turn the key to run, the relay will turn the TCS on and off.
Video
This mod is useful for all 05-09 GT owners, especially people with F/I, as the TCS pulls fuel instead of spark. Even though TCS can be disabled via tune, it leaves an annoying light on your dash and its not able to be turned back on via the button. Wiring a relay in allows you to retain use of the button, as if there was no relay.
What I used:
3 colors of 18 GA wire
Package of crimp on female connectors
package of wire taps
regular relay
add a fuse
10A fuse
zip ties
3M two sided tape
shrink wrap
You will need to disassemble the center console. Remove the upper console piece by unscrewing the 2 screws under the center console lid. Lift up on that and remove it from the car, or just position it out of your way. You will then have to remove the two side trim pieces on either side of the radio by pulling them straight towards you. Once you have those removed, you have to unscrew the 7mm (6) screws that hold the finish piece on over the radio. You can either remove the whole panel by disconnecting the 3 plugs on the top and the 2 on the bottom, or just try to work around it.
I first tried to tap into a source that was hot only on start to avoid using an add a fuse. I was unsuccessful, so I tried using an add a fuse. I tapped into a hot on start fuse with the add a fuse. Fuse 20 in the smart junction box. Its in the passenger footwell. Put in your add a fuse and connect one color of wire to the end of the add a fuse. I chose to use red.
Next I ran my hot wire along the firewall to the center console. I attached it to another harness with zip ties.
Connect your red wire to the relay on terminal 85.
Next you will need to ground the relay. You'll want to splice two pieces of black wire together so that you end up with two places to add female connectors and one longer length of wire to run to the metal center console bracing to ground the circuit. Slide a piece of shrink wrap over each piece of bare wire, crimp on a female connector, slide the shrink wrap over it, and shrink it! Plug these female connectors on to terminals 86 and 87 of your relay. Unfortunately I didn't get a picture of my finished product, but here is what it should look like before the female connectors and shrink wrapping. The longer "tail" is what will be bolted to the center console. The other two ends get connectors and shrink wrap
Now take your last color of wire and one of your wire taps. Locate the TCS wire. You'll be looking for YEL/PNK or WHT/PINK. Its pin #7. Now you will want to place the TCS wire and your last color of wire in the wire tap and press the metal guillotine down with a pair of pliers. Snap it shut and run your wire down to the relay.
Once you have enough wire to reach the relay, snip it, strip it, add a female connector and shrink wrap it. You'll plug this into terminal 30 on the relay. Once you have all your wires connected, you will ground the relay and you can mount it right by the ground. I used the bolt in this picture behind the wiring.
All I did was take the bare end of the black tail and loop it under the bolt. You could buy a crimp on loop at radio shack if you want. I then took a small piece of 3M tape and taped it to the metal support of the instrument panel. Before mounting, make sure the relay is working!
The relay will flip the switch when you try to start the car. All you have to do is turn the key to run. If the relay is working, your TCS light on the TCS button will light up. If its not working, the light will stay off. As you turn the key to run, the relay will turn the TCS on and off.
Video
Last edited: