Cruise Control

yayo_ayala

Registered User
Hi guys, I finally fixed some issues in the speedometer and the ABS sensors. I tried the Cruise Control (CC) but did not work. I reviewed the Manual and tried to start testing connector C207. I have a manual for a 92 and my car is 91 - I am assuming they are the same (please let me know if I am wrong).

I look under the dash and this is the only cable that matches the description. But the manual describes a blue cable and none of those matched (green, red, yellow and black). I will appreciate the help in identifying the C207 or CC in general.



Thanks!

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looking in the wrong place

Thanks for the guys who told me that I was looking in the wrong place. The connector C207 is color GRAY and located in the brake pedal. I checked with a multi meter the resistance. Comparing the information from the Manual and moving the steering wheel -everything is in parameters (Review previous photo for the parameters).

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I follow the instructions, and the manual has indications for the connector C256. It is color WHITE next to the gray. Unfortunately I don't have any resistance (infinity reading), the circuit is open.


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In terms of the Modulating Valve, I found in this thread
http://www.sccoa.com/forums/showthr...ht-always-stays-on-cruise-control-not-working

here are four causes for the Speed control to be inoperative. The modulating valve is faulty(Servo Motor Open). The Dump Valve is faulty at the pedal. There is no vaccum source(Or leak) at the Servo. Or an open circuit for the speed control switches on the wheel. You need to locate connector C109. It is located in the area behind the passenger headlight. I know this sounds silly, but that harness runs all the way across the header panel and over to the drivers fender well to the servo. It is a blck connector with 6-pins. Disconnect it and measure the resistance of the Orange/Yellow wire and the Gray/Black wire. Then measure the Orange/Yellow and the White/Pink. Both should have values between 40-125 Ohms. If that is Ok then your Modulating Valve (Servo) is Ok. Make sure you are measuring the correct side of the connector to the Servo. If all is Ok there Measure Voltage (Key On!) between the Light Blue/Black wire and the Black wire while someone is depressing the on switch on the wheel. If voltage isnt there you need to check the Yellow/Light Green wire for an open betwwen there and the column. If you have no voltage and the horn works I would suspect the Switch assembly itself....Other than those two things you need to recheck the dump valve and make sure you have vacuum at the servo.....Hope this helps...
And I have never seen an EEC issue with inoperative Crusie Control....Ever!!! And I have worked on a couple lets just say!



I couldn't find the connector C109, I don't think it applies to "Modulating Valve". Any advise at this point is very welcome...
 
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Have you removed the horn pad on the steering wheel and verified those connections are healthy? Horn works ok?

Going back to your A/C, you found a loose connector, as I recall - has the dash been out of that car? Was it swapped in? Does it have an aftermarket stereo? Alarm?

Can you see the multi-wire connector for the ignition on the side of the steering column? Is it opening up when you turn the key?

I'm not saying those are/aren't directly related, but you seem to have uncommon root causes so far, so it might help to not limit yourself to otherwise trusted troubleshooting procedures, and look for -anything- that might be out of place, etc.

Is the cruise control cable connected at the throttle body?
 
Thanks KTM

Hi KTM, thanks for your inputs. About your questions:

Have you removed the horn pad on the steering wheel and verified those connections are healthy?
Yes, I removed them and checked them. Those connections go to the break pedal and they are part of Connector C207 (Gray connector). I unplugged it and checked the resistance and turned the steering wheel - everything it is in parameters.

Horn works ok?
Yes it works.

Going back to your A/C, you found a loose connector, as I recall - has the dash been out of that car? Was it swapped in? Does it have an aftermarket stereo? Alarm?
- No, no aftermarket stereo, or Alarm. I am pretty sure the problem was the speedometer, it was not working. I have the impression that the previous owner tried to fix it and removed the dash and did not take the time to put all the connectors back in place. The gentleman who fixed the speedometer, in addition fixed the high beams and few other things that were disconnected. I connected the sensor and removed the E3 problem.

About the AC. I bough R12 and I might get it before the weekend. I will go with a friend that has a way to check the pressure and hoses for R12 and in case it needs refrigerant we will fill it.

Can you see the multi-wire connector for the ignition on the side of the steering column? Is it opening up when you turn the key?
- I am not sure, but wasn't that the connector that I was previously checking - the one that I was originally confused with the C207 (beginning of the post).

I'm not saying those are/aren't directly related, but you seem to have uncommon root causes so far, so it might help to not limit yourself to otherwise trusted troubleshooting procedures, and look for -anything- that might be out of place, etc.
- I agree. the previous owner was not using the car; but when when he was fixing something, I got the impression that he started testing and just left unplug multiple things.


Is the cruise control cable connected at the throttle body?
It is, I already checked that portion.


KTM, I think in this moment there is no reading for the "Modulating Valve", And I need to fix that problem before I move to the next step. But before I remove the front cover fender - I am wondering if there is something else to check. In my previous comment there is a link to a thread, and they are talking about connector C109; located in the area behind the passenger headlight..... I don't see it in the manual or looking around that area. Tomorrow, I will remove the cover fender and search for the "Modulating valve"

Thanks KTM
 
I don't think I see the ignition switch in your images.


Looks like this:
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Bolted to the side of the steering column with security torx screws. There is a lot of tension inside and many connectors...when they get a few/several years old, they tend to come apart when you turn the key with the results affecting several circuits. Not too expensive, my advice is to treat it like a wear part and replace if age unknown.
 
A very common problem with cruise control is breakage of the cruise control servo. The servo is located in the driver's side front fender well. See this thread: http://www.sccoa.com/forums/showthread.php?105006-Cruise-Control-Problems

It usually breaks the piece that attaches the servo diaphragm to the cruise control throttle cable...most likely due to a mis-adjusted cable.

You can replace the servo and then adjust your cable up at the throttle body. I would also recommend checking/adjusting the vacuum switch on the brake pedal. It can get moved/dislodged and prevent the servo from working correctly.
 
thanks tberger06

Thanks tberger06, let me tell you what I did today.

Today, I checked the connector that I think it is C109 (I am not sure if it is C109 or other). This connector is located in the front of the car, it is behind the headlamp on the driver side (I will call this connector C109)
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The connector C109 has the same color combination as C256; using a long cable, I checked the continuity and it worked. (I am glad that I don't have cable issues from this place to the steering wheel).

After that I checked the other side of the connector, the side that goes to the Servo
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Before removing the servo, I did not get any reading in the multi-meter (infinity). Once I removed the servo, I got the readings that I was looking for (60 and 130 ohms).... I don't know if shacking the servo, or moving it from the bracket helped.
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tberger06, I will continue testing next week, once I fix some problems with a belt tensioner. But I am glad that I finally have the readings for the servo.
 
Break Pedal

Last week, I retook the activities and thanks to all the inputs. I checked the brake pedal and even when I was not depressing the pedal, it was not depressing the switch; I am guessing the valve was open. I already adjusted it (below images). Today I will follow tberger06 and check the breakage of the cruise control servo.

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DEPRESS Brake

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Servo

Today I checked the Servo. I removed the linkage at the throttle and checked the servo.
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The servo looks fine.
I checked with an ohmmeter and the reading are correct (for the parameters, I documented it at the beginning).

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The vacuum hoses, the black and red (B/R) has vacuum power, the black and yellow (B/Y) there is no vacuum. I am guessing B/R is coming from the engine, and B/Y is going to the brake pedal.
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Servo

I used a vacuum generator, I was able to retract the diafragma, but after 2-3 sec, it doesn't keep it, it returns to its original state.

I am not sure about the pedal, if the switch is correct or if there is a way to test it?

should the servo retain the vacuum?
 
should the servo retain the vacuum?
Yes - if it doesn't hold vacuum when you block off the BK/Y port, it seems to have failed.

The valve at the pedal should vent/open to the atmosphere when the pedal is pushed.

Put vacuum to the line that goes to the pedal, make sure it holds, then press the pedal to confirm the vacuum is lost.

The amount of rust on the servo housing is not a good sign.You may need to swap in a known good unit to test.

TBSC Shop has a used one on eBay for $58.

Sorry if I missed it, what is the vacuum at idle?

Good luck.

Ken
 
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