02 toyota corolla, CCS-100

I have installed a CCS-100 Audiovox (vacuum) in  my 1995 Ford succesfully and I tried to install one in an '02 Toyota Corolla (manual 5-speed transmission). For the life of me, I was not able to locate functioning tach and VSS wires. The cruise circuits all check out fine according to the tests in the manual and I tried all possible combinations according to the manual and what is available on the Internet, but the unit just will not engage. I think I am not getting a proper tach signal. The current settings use the "tach only" for manual trasmission taken at the diagnostic connector (black wire), which does not have an IG- lead (like in my Ford). I was looking for the distributor and the coil, but could not find a the "black wire" there either. Please, help! This is killing me...

Actually, I was able to answer my own question and solve the problem by some more thinking and trial. All of you out there, who are completely frustrated with the CCS-100 manual that is sooooo bad, and usually neglect the crucial differences between automatic and manual (like no one buys 5-speed cars...), here is a solution for getting a great tach AND VSS for an '02 MANUAL(!) Corolla:

1) You rip off the central dash panel, below your radio. On the very bottom (almost on the floor) there is your ECU sitting in an impossible position. If you are patient enough you can unscrew it and turn it, so that you have direct access to to 3 plug connector on the ECU (yes, NOT 4 plug as some manuals state -  that is for the automatic Corolla).

2) Last big grey plug on the right (22 pin) has a purple (some refer to it as violet) wire with white lines on it. This is the only cable with this color combination. That is your VSS signal (gives you the speed of the car relative to the road). The best way to tap into that wire due to the bad position of the ECU is to use the blue connectors that came with your box. Connect the grey wire coming from your servo (runs with the black wire in pair). These connectors do a reasonable job.

3) Now, go back to the 1st grey plug (first from the left as you look at the ECU) 3rd wire from the right in the top row is a blue wire with yellow stripes. That is you TACH (engine RPM, ignition, whatever you call it) meaning that this gives you the engine's speed. You can even measure it (and here is another piece of info that you will not find anywhere) by using a combined digital voltage meter in the AC position (since the signal is a pulse with a frequency proportional to the RPM). When in idle, you should measure about 9V steady in AC. As you rev the engine voltage on the meter should go DOWN slightly, as the frequency of 0V periods increases (pulses are squares from 0-12V).

This setup gives a very reliable, nice and smooth cruise action. And no, if you set your speed in gear 4 and then brake (disengage cruise) then go to gear 5 and hit resume, it wil NOT accelerate over the set speed limit, because the purple and white wire supplies the VSS signal (car's relative speed to the road) no matter which gear you are using. That is one more reason why you should NOT use the automatic settings on a manual car and and similarly, you should not skip the VSS signal and use just tach, if posible.

Here. You have it now.

Thanks sparkie. Except, I never use the cruise in a gear other than 5. Why would I? Here in Oklahoma, you don't need to shift back from gear 5 on practically any highway. You switch to gear 5 over 50 MPH and you are done with shifting. :) This makes the clutch switch unnecessary (for me). Thanks anyway.

Sparky,

Yes, you were probably right. After some extensive testing I discovered that the cruise unexpectedly disengages under certain conditions. This happens rather in a "train", meaning that it works fine for a longer period of time and then it starts quitting regularly. Next day it is back in the "mood" again. I tried to track down the source of the problem or the conditions under which it was happening, to no avail. If this is really a sudden spike on the TACH line as you say, why should selecting the TACH only option help? One would think that it makes the problem worse. If I select the TACH only option now, the unit does not even engage.  I had to connect the servo to the gas pedal, since this car is not suitable for a direct connection to the throttle. This causes some additional curvature in the servo line which may affect cruise operation. It appears that low outside temperature also has to do with this problem, but I was not able to measure this accurately. I appreciate your insights.

Zsolt

Thanks Sparkie! I used the pedal linkage because the manual said we should do that (without the adaptor you can not really do it reliably), but I will probably switch the link over to the throttle. This adaptor costs only $15, so it is really a good deal. When you say you use TACH only on this model, where do you exactly tap into a good TACH signal other than the one on the ECM? I was not able to find one and neither the manual nor the guy at Audiovox was able to give me decent information.

Thanks again!

Zsolt