Swapping to SR20? Want to keep your cruise control? Read on!
Time: 1.5-2 hours, not including harness/ECU removal and installation (if necessary).
– heat shrink tubing or electrical tape
– zip ties
– paper clips
– cruise control throttle cable and pulley or material to fabricate one
– spare s14 KA harness
– 10mm socket wrench (if removing or installing ECU)
1. Disconnect your battery.
2. Remove the passenger side foot-plate and then the ECU cover. They should pop right off and I believe there is a plastic nut holding the ECU cover on up under the dash.
3. Unbolt your ECU, there should be 2-3 nuts, one right inside the door and one in the same spot that plastic nut was. Pull the ECU out of the way, you might even want to remove it completely for better access.
4. Gain access to your F1 connector, body harness, whatever you want to call it. It’ll be located behind the ECU in the back corner. It should look like this and it will have the wires leaving the connector out of the top(inside the car).
5. There will be a plastic latch that holds it in place. You must remove the latch before you can pull this out. Pull the connector out and get it to where you can work on it fairly easily. There isn’t much room to pull this connector out, so most of the work will have to be done with your head underneath the dash.
6. Pull the black cover off and expose the wires. I already have the 4 wires you need separated from the rest.
They are, in clockwise rotation, starting at the top left; Blue/black, blue/silver dots, blue/white, and green/yellow.
7. With a small screwdriver pry the gray clip out (this holds the wires in from being pulled or falling out).
8. You’ll next have to pin the wires out. Use a paper clip or a screwdriver for glasses, it needs to be very small. On the side of the clip you’ll see little tabs holding the wires in. Lift each tab and slightly pull on the wires to remove them. Do not forget the order they go in. If you have to, label them or even print this out if you have too.
9. You’ll have to cut open the hacked KA harness to get these out. I used a razor and cut all the black electrical tape to gain access to these wires. You’ll have to also cut the rubber grommet that seals the interior from the engine compartment. They used some sort of expanding foam here, just take your time and becareful not to cut the wires, otherwise you’ll be splicing.
10. Once you’ve removed the wires, tape them up. Just wrap them in the electrical tape and make it look neat. Might as well take the time now while it’s out of the car.
11. Connect the cruise connector to the cruise unit. It’s located in the passenger side of the engine bay, mounted on the back of the strut tower and bulkhead.
12. You can either cut a small hole in the rubber grommet to pass the cruise wires through into the interior or drill a completely new hole and add a grommet with that, to seal it. I just cut a small hole into the harness’ rubber grommet. I used some electrical tape and a clothes hanger to get it through.
13. Pull the wires into your passenger footwell, undo the tape or whatever you used to get them through the grommet. Now, just like you did to the KA’s F1 plug, you need to do the same to the Sr’s F1 plug. Pull the black cap off the Sr’s and pry that gray piece out. I believe that the Sr’s top 3 or 4 holes are empty, there might be 1 wire on the right side of that connector, located where the Blue/White wire would go( I think mine was Orange), go ahead and pin that out(you can move it down a spot if you’d like), it does nothing (Per Yuri at WiringSpecialties). Once you’ve got the 4 slots open, slide the cruise wires in one at a time in the original order they were in the KA’s harness. From the top left in clockwise rotation Blue/Black, Blue/silver dots, Blue/White, and Green/Yellow.
Once this is done and you check over the wire orientation again to be sure, slide that gray piece back into place and put the Black cover back on.
14. Plug the F1 connector back into its holster and flip up the plastic clip that holds it in place. Finish bolting your ECU back in and reinstalling all the covers.
15. Move over to your driver’s side. Yes you have work to do over here as well. You need to add a jumper wire to the ASCD switch connector if you had an auto car before the swap(reasons further down of why).
If you had an auto car you had an ASCD cancellation switch located on your brake pedal. This is what the switch looks like.
While cruising, if you tapped the brake pedal, the cruise would disengage. Same thing still applies as you are using the existing unit in the car. The switch for the ASCD is normally open, when the brake pedal isn’t pressed it would make contact closing the circuit for the ASCD. Well, I had to eliminate that because there wasn’t a spot to put this switch on my 5spd brake pedal. If you have the means to do this please install the switch, it’s safer and is how the system is meant to work. Since, Yuri at WiringSpecialties.com did my harness for me, I didn’t need the switch, only a jumper wire, because even when my brake pedal is pressed the ASCD system shuts off and retains normal operation without that switch. Normal operation being, foot to pedal driving. If you already had a 5spd before the swap, you shouldn’t have to wire anything over here.
16. Now that all the wiring is done, you need to make some sort of bracket to hold the cruise cable. I have access to aluminum angle so I just made a simple bracket out of 2″ x 1/16″ angle.
You’ll also need to make a custom pulley to be added to the side of your throttle pulley, as we all know the Sr didn’t come with cruise. I used a KA’s cruise pulley and cut it down(mounting flanges off), as there isn’t enough bolt sticking out to bolt it to the throttle plate, that meshes with the TPS. I also used pieces of tube stainless steel to weld it to the factory throttle pulley. I simply lined up the holes where the wire slides into the pulleys with a rod and tacked everything together. It may not be pretty, but it gets the job done.
This is what worked for me. It may work for some but not for all. If you’ve had your harness converted by Yuri, everything in this post should result in working factory cruise on your Sr’d car.
I am not responsible for any damages that may occur to your car. I’ve had no problems with mine so none of you should either. Good luck to any and all that try this.