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Topic: cruise control (SOLVED) (Read 9368 times) previous topic - next topic

cruise control (SOLVED)

Reply #15 –
Applying voltage to 144 and grounding 146 will close the vent valve.
Applying voltage to 144 and grounding145 will open the vacuum valve.
You need both to let the vacuum operate the servo.

cruise control (SOLVED)

Reply #16 –
so in your opinion,, since i do not have the amplifier connected and i want to do a dry test with the engine off.......
do you think it would be ok to keep the previously mentioned "momentary" ground connected long term just so i can get the modulator wired up so its open?

I want to pull my own vac with a pump and also check that variable resistor.

cruise control (SOLVED)

Reply #17 –
Yes I think that will be ok.

cruise control (SOLVED)

Reply #18 –
Quote from: ZondaC12;195362
Oh my God F this. LOL but seriously I love how there's about 1.3 million different things it could be. I'm seriously reading this all and shaking my head.



no, it really isnt all that complicated, im just good at over complicating simple stuff. I already know for a fact the servo is defective or the cable is undone and thats been known since probably my second post.  All i wanted to do was learn the entire deal, that way i can manage to write up a simple diy for quick testing.  So far , i think ive managed a single test that will do that.

dont give up so easy man:D

cruise control (SOLVED)

Reply #19 –
Quote from: softtouch;195497
Yes I think that will be ok.


Yep, your right!! im glad that was your answer cause i did it.  I was able to do a dry test on the system with no engine running.  I appiled power to circuit 144 using the floor light connection as my source and of course, grounding circuits 145 and 146 was easy.

Results:
I was able to apply vac presure to the servo and with my ohmmeter hooked up to the pins tied to the variable resistor, i was able to see the resistance change as the servo moved.

Did i see my throttle likage move when i applied vac to the servo hose----NO
Did i fail any voltage and resistance checks--NO
Did i fail the test in the shop manual where they say to momentarily touch circuit 145 to ground --YES
I swapped in a known good amplifier and did the results change-NO
After letting a large amount of WD40 flow down to the servo, did i see any change--Yes- when the vac pump was removed the servos resistance check showed it retracted quicker than prior tests so it was slightly binding.
Did the vac dump valve operate when the brake was pressed--YES
Did the servo modulator portion hold good vac pressure--YES

In all honesty, the servo isnt failling i dont think nor is the modulator
Something tells me the servo and the amplifier are doing the correct job(s)
Its likley the cable is undone at the servo and thats all.  This does not account for failing the operational test though.

I need a volunteer to do a simple test on thier car which will verify my simple three step check for the operation of the cruise which will take only 30 min of your time.  All in all this have been an intersting venture into the cruise operation and im pretty comfortable now with what needs to be done to fix the problem.

tools required are:
small flat blade screw driver to pry off the two connectors.
vacuum pump hand held
one meter
5 aligator clip jumper wires


What i learned about the amplifier box-
You best just pop the back off and extract the circuit card.  The color codes for some wires in the shop manual and the evtm do not match.  However, the circuit numbers are stamped on the amplifier circuit card and if you just use that as your guide, you will know what wires to do what with.

I will do an easy write up if anyone wants to test thier system.  I would prefer a working system to verify the one step the shop manual calls out just to see if the manual is incorrect or not.  Shop manuals are not perfect.  My white cougar is currenlly down due to my pending project which parts are arriving /have arrived.  Thank you TOM and thank you Greg Hoag at MegaSquirt.

cruise control (SOLVED)

Reply #20 –
Well, its nice to see that people want to pitch in once in a while to learn a couple things on thier cars. 

Thats ok,, someone has a broken cruise out there somewhere who's not too lazy to dig in without giving up.  If no one wants to do a simple stare and compare test, thats fine with me.

cruise control (SOLVED)

Reply #21 –
Haha I will probably dive into this once again in the near future. I REALLY would like to have it. NICE tip there about the amplifier. I found the same thing, couldn't figure out the numbers, nothing matched!!! I just skimmed over that big post, I'll read this thoroughly and perform the same tests when I try it again. Honestly I can do all that just lots of text like that = me skeeeered. LOL
 
Next semester doesn't start 'til the 14th though so I got this week, and it's supposed to be rather nice maybe I can work outside! Lemme know what I can check out.
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

cruise control (SOLVED)

Reply #22 –
if you get into this,, call me.  see diy link

cruise control (SOLVED)

Reply #23 –
I have one complaint here,,

if you look at the evtm page i posted,,, Why in the hell do i not have continuity for the "ON" portion of my cruise from circuits 6 to 151?

When i push the on button, i should have a continuity path and i dont.  However,, when it comes time to test the on button for power delivery according to the directions , all is working fine.

cruise control (SOLVED)

Reply #24 –
Problem solved. 
First pic is of the problem.  The cable was not connected to the servo assembly and the clip it connects to was ripped.  I will tig weld that tomorrow.

Second pic
I had to figure out a way to get slack on the cable to come to me:D .  Same tool i use to hold presure on the brake pedal when i bleed them. :hick:

third pic
The broken clip and that wee tiny little snap ring.  I reshaped it as close as possible in prep for tig or brazing tomorrow.

SInce all my tests prove out, and i found the cable unhooked,  Problem is 99% for sure solved.  Too much snow now to test out, much less get it out of my 1460ft driveway.

Here is what i think happened for the failure.
Since the cable is only there to "PULL" on the clip and  de-actuate the servo or to accel, I belive that the trottle body end got in a bind during the time when the PO installed an HO upper/lower intake.  Somehow the cable got yanked out of the clip and now you see the results.

What did i learn?
To test if the cable is connected, you should go directly to the throttle boday and disconnect the cruise cable.  push on the cable and let it go.  It should pop back out on its own because the servo spring will push the cable back.  This is only true if the little ball fits or snaps into the loop around part of the clip.,,,(atleast mine will when its all said and done)

I also learned to stick to the simple stuff.  If the controler does not fix the cruise and the switches are good and verfied along the underside of the steering column, then there is likely an issue with the cable.  I would venture to say the cable is a large percentage of other peoples faults as well.  Just remove your wheel, fender skirt, two screws holding the servo and two nuts holding the cable assembly on.

cruise control (SOLVED)

Reply #25 –
Good show!! Perseverance usualy pays off.

Can't see why your resistance check of the ON switch didn't work.

One interesting thing I noticed while studying the EVTM is the source of the voltage for the ON switch. It comes through the coil of the horn relay. In other words it is the side of the coil the horn switch grounds to pick the relay. If the horn relay coil were open, or the relay unplugged, you could not turn on the cruise.
That's why at one point I ask if the horn worked.

cruise control (SOLVED)

Reply #26 –
Quote from: softtouch;198509
Good show!! Perseverance usualy pays off.

Can't see why your resistance check of the ON switch didn't work.

One interesting thing I noticed while studying the EVTM is the source of the voltage for the ON switch. It comes through the coil of the horn relay. In other words it is the side of the coil the horn switch grounds to pick the relay. If the horn relay coil were open, or the relay unplugged, you could not turn on the cruise.
That's why at one point I ask if the horn worked.



yeah, and when you said that,, i knew my horns both sounded kinda funny but got better after i worked them and used the car.  It has sat for a while.

that part of the diagram is really stupid confussing.

cruise control (SOLVED)

Reply #27 –
well, tig welded the braket clip and it turned out good.  Pic wasnt the best in the world but the clip is just fine:hick:

The driveway froze back up since it was late getting everything back together.  Since the driveway is about 1,450 feet long all down hill, i figured id be smart and hold off till the daytime so i can get back up to the house.

test time tomorrow.  everything went together just fine.

cruise control (SOLVED)

Reply #28 –
driveway still like a skating ring ,, not safe to attempt a return trip up the driveway, muchless down.

this is killing me waiting on some slush to happen.  Its like 9degF out there right now.

cruise control (SOLVED)

Reply #29 –
I finally risked getting "Anny" down the driveway and it took six full minutes to do so feathering the Ebrake and steering the tour down hill.

I finally get to hard top,, I light up a good luck smoke and take a sip of coffee and top that off with ice breaker candy.  I settle in preparing to be pampered by cruise control.

I press on
then i press set/accel and nothing.

I think back to the condition the switches were in and i repeat the above but add more presure to the switches.

IT WORKS!!!!!!!!!!!!!!!!!!!


Im sitting there just enjoying the thoughts that just in time for my road trip back to spartanburg sc, my cruise will take me there.

I look down and think,,himm,, leme wait for an up hill area and see if my cable is adjusted correctly. If my speed decreases to a certain level, passing gear should kick in before the cruise lets out.

Well,, i decide to decline on that thought because i could not wait to work the button.  I pressed set / accel and nothing.  It felt like set/accel shut down the cruise. 

SO,,,, I press ON followed by set / accel and nothing again.

I press ON followed by set accel again and nothing.

As a matter of fact i think i pressed ON followed by set/accel pretty much for the six mile trip to the corner store before i gave in and said,,, "scott, give it up".


This is odd so i will look into this matter in the future.  I have to stew on this for a while and figure out what would have cause it to work once then never again. 

I will check my cable again as well as swap out amplifier modules.
If the cable and amplifier check out ok, then I will be foreced to replace the servo.

while i had the servo off, i noticed the servo wiring harness was fabricated to the servo itself with a pigtail long enough to reach the amplifier.  I suppose i could take the servo apart but i will not do that until i determine the servo is good or not.

anyone wanna slush me an amplifier?

one other thing, I could have criss crossed the vac lines going to the servo but they are pretty easy to tell apart.  one will not reach the others fitting.  Oh well,,, to be continued. 

I am going to leave the word "solved" in the tread title because I did locate the problem,, now it appears i may have to figure out what caused the problem since my prior conclusions were likely incorrect.