One of the consequences of the 2AR-FE swap being drive by wire is that I was able to retrofit cruise control into my 2003 manual Spyder and it looks completely stock.
Here is what to do:
1. Find an early 2000s Toyota in your local salvage yard, preferably a car with the same steering wheel as the Spyder- Celica, Corolla, Spyder SMT, etc. Buy the clock spring, cruise control lever, and steering wheel backing with the opening for the cruise lever. If you don’t have any pins left from rewiring your harness, grab a connector off the ECU with the smaller pins. I took all of this off a 2003 Celica.
2. Remove your steering wheel after disconnecting the battery and removing the airbag. There are Torx screws on each side to release the airbag. The clock spring is held in by three clips, at 12, 4, and 8 o clock.
3. Replace the rear shell on the steering wheel.
4. The manual Spyder steering wheel has the holes for the cruise lever, but they aren’t tapped. It’s M5x0.8.
5. At this point it is probably smart to measure the resistances of your cruise lever and make sure they match the tC lever. Mine were the same.
6. Attach the cruise lever to your newly tapped holes and verify the clock spring is functional- if you look closely the stock clock spring (left) only has 2 pins and the cruise control has 5. Make sure the two pins of the cruise stalk, pins 2 and 3 in the Celica, carry through. My pin #2 wasn’t giving consistent readings, so I relocated the lever pins to 3 and 4.
7. Reinstall the clock spring and the steering wheel into the car.
8. Next, you need to run a pair of wires from the clock spring to the body controller. At the clock spring side I depinned pin 4 on the connector to the right and connected my scavenged pins on pins 3 and 4. Thanks to Paul Hibbs for the photo and guidance. The red and white wire is ground and none of the other wires are used in the Manual Spyder.
I routed the wires next to Marc’s drive by wire harness.
On the ECU side, I connected one of the wires to body ground, and the second wire goes into pin 19 of the 22 pin connector- use your leftover pins.
This pin gets routed through the body controller to the cruise pin on the ECU.
9. So, now you have cruise, and brake (provided by the body controller already, thanks Marc). The last piece is the clutch signal.
In the Spyder, the clutch switch flips between Open (Clutch out) and GND (Clutch in):
The tC expects 12v (Clutch out) and Open (Clutch in):
The current version of the body controller doesn’t do this automatically, although I will be testing a white wire mod. Until then, you can tie the clutch wire (the green wire- I am not sure if it is in auto trans harnesses, because I used a manual harness) going to the ECU to one of the Ignition wires on E4-
This will make the ECU see 12V and let you set the cruise. It won’t disable cruise when you push in the clutch like the eventual correct wiring will, but who pushes in the clutch while in cruise?
Now you will have functional cruise control with a completely stock appearance.
The only thing at this point is the cluster won’t show you when you have cruise on or set. I don’t know if the stock cluster has the lightbulb and a CAN message needs to be sent, or whether somebody could wire up a switch to an LED, or ...
The light will be a CAN message and interestingly I have an extra driver on the body controller to drive the security LED. Having the cruise light under the fan speed knob is a bit off but some software could fix what you're asking for.
It's not going to happen right away though, working hard on the A/C compressor and the 2ar-fe build right now.
I would be fine with soldering down a LED and drilling a hole in the overlay if you can figure out the CAN message... after you finish everything else.
A bit more looking, the cluster PCB is also missing a resistor, a transistor, a capacitor and a resistor so you would need a custom overlay and a modified circuit board. I could actually do both but that overlay is not super cheap to get done.
That particular position looks like it goes to a discrete pin but interestingly some of the other unused positions look like they may get controlled over BEAN to avoid needing to wire in anything extra.
It would probably end up being a $200-300 cluster upgrade service which seems excessive for a cruise control light.
That would work. I was thinking a trigger to ground relay that switched an LED on/off. One could wire in the cruise control signal, which is turned on/off by a pulse to ground and use that to control the LED.
Or, just route the logic into a pin that will drive enough current to run a couple wires from the body controller to the dash somewhere.
It just occurred to me on the missing clutch switch that an inline brake pressure sensor would work great. those are designed to close contacts at low pressure and designed to handle way higher pressures than a clutch master produces. Plus they use the same fittings as the clutch line already and the sensor could be placed near the ECU area to avoid wiring all the way to the dash anyways.
You just need one side of the switch to go to ground and the other site to go to ignition through a 2-5k resistor and that same 2nd side to go to the ECU's clutch switch input.
I’m going to take a look at the clutch pedal and see if there’s any existing threading... I imagine there has to be for another stock Toyota part, like this.
I'll save you crawling around in uncomfortable positions. it's much easier to see it on my race car without a dash. You absolutely can use a switch like that, that style replaces the top of travel stop bolt that you can see here:
It just occurred to me on the missing clutch switch that an inline brake pressure sensor would work great. those are designed to close contacts at low pressure and designed to handle way higher pressures than a clutch master produces. Plus they use the same fittings as the clutch line already and the sensor could be placed near the ECU area to avoid wiring all the way to the dash anyways.
You just need one side of the switch to go to ground and the other site to go to ignition through a 2-5k resistor and that same 2nd side to go to the ECU's clutch switch input.
This kind of thing:
This style switch was used in many mid fifties and sixties cars. They work fine but the new switches have a high failure rate unless you buy very high quality. I had to replace mine on my 57 Tbird and purchased a Ron Francis switch. I hope it works for a long time.
if they fail in Cruise Control system when you hit the brake the car can accelerate.
Is the threading the same as the brake light switch on the brake pedal? I’m not going to go to the salvage yard looking for a manual car, but I know there are early 2000s Toyota’s if I can use the brake switch for the clutch.
This style switch was used in many mid fifties and sixties cars. They work fine but the new switches have a high failure rate unless you buy very high quality. I had to replace mine on my 57 Tbird and purchased a Ron Francis switch. I hope it works for a long time.
if they fail in Cruise Control system when you hit the brake the car can accelerate.
They also got used in 90's and early 2000's fords for cruise cancel so there are more modern reliable versions available. Also, it's a manual transmission so i'm not really worried about cruise killing anyone. Just push the clutch in if something goes weird. I've actually had this happen to me in a 2001 ford ranger back in the day. it started accelerating and instinctively i pushed the clutch before i saw the RPMs flare way up and realized what had happened. A Cruise failure in a manual transmission vehicle is merely an inconvenience.
Michael, i just went and measured it with calipers and it's an M10x1.25 thread and it looks like there's an 8-10mm thick captured nut and about 10mm gap before the plate so the sensor needs to be at least 20mm long plus whatever the jam nut thickness is. Also, my pedal seems to be missing the rubber bumper. if yours is missing you'll also need part number 90541-06036 to replace it.
But I can do a bit better than that. the part number you need is 88280-14030. cross referencing the part on e-bay i found this: https://www.ebay.ie/itm/Clutch-Switch-Lucas-SMB5018-Replaces-88280-14030-/362746208102 which confirms the thread to M10x1.25 and it has about 30mm of thread. It's also used in the 2010 camry so it's even the right switch for the 2ar-fe (not that there really would be a wrong switch, we could use normally open or normally closed)
