1998 Mercury Sable Cruise Control

Ok we will do some tests to see if the buttons are working but first I need to know if you have a digital multi meter? It has to be digital as the computer system does not like using anolog type. Get back to me with that and we will do a couple of test to determine if it is the wheel or the vss (vehicle speed sensor) or the brake light switch ok.

I don't have a multimeter anymore. I did have an analog one, but it didn't work very well. I will get one of those as soon as possible.

I checked with my local Ford dealer today, and they were unable to help, as it's an older vehicle (+10) years. I guess if I had tried last November I could've gotten some help.

I'll get back to you on the multimeter.

Ok make sure it is a digital as the computers don't like anolog type. It does not have to be a fluke or anything like that just a one that has volts and ohms and such a 25 dollar one works just fine. Once you have get back to me and we test the system.

I have it. Got me one for $23 at Lowe's last night.

Course on the way home, a brake line on another car went by-bye's, so I'm dealing with that as well.

But anyways continue. I did get a Digital one, as I never could understand the analog ones anyway.

OK first things first lets see if the car will tell us where to look first ok. The steps I am going to give you will make the car do a self test of the cruise and give us any codes to get to a place to start ok.
1) Put the car in park and set the e-brake do not put you foot on the brake pedal. Now while holding the cruise off button turn the key to the run position (key on engine off). The cruise light on the dash should flash once to tell you it is self diagnostic mode. If it don't flash then repeat.

2) Release the cruise off button and within 5 seconds press the cruise on button. Now press the remaining buttons in this order. ON, RES, COAST and SET, and ACCEL. As you press the buttons the CRUISE light will flash, Wait till the light goes out to press the next button. After you done doing this test and all the buttons have been pushed the CRUISE light will flash you need to count the flashes. Once that is done the car will do a throttle test and will open the throttle just a touch. Once that is done then the self test is complete and you can turn off the key. It will flash 1 to 5 times. Get back to me with the number of flashes and we go from there.

So I tried that.
I got in the car, brake on, and held "off" button for 5 seconds, turned car to run, then hit the "on" button, then the "on" button again and each time the Cruise light flashed once. However upon each attempt at getting the "Resume" button to get the light to flash, nothing happened.

I wonder if I wasn't supposed to press the "on" button twice, as indicated earlier. I will try that in a bit as soon as I warm up.

You gotta do this fast, and get it done rather quickly, like playing SIMON.

But anyways it was only one pressing of the "On" button, and everything else worked (so I don't have to replace the buttons).

Subsequently, I received "1" blink extra. I did it three times to make sure, and it was most definitely, a 1.

That is great that means it passed that is what the one blink means so it is getting all the inputs from the wheel and the cruise module understands it. Now we need to test the VSS Vehicle speed sensor. I am thinking that may be your problem as to why it won't work. Are you ok with doing some tests on the ABS unit and such? Let me know and we go to the next step.

Here's the funny part to that answer.

I'm comfortable testing anything. Unfortunately I don't have ABS. Yes it listed that the car had anti-lock brakes on the thing when the 2nd owner bought the car, but when I went to do a brake job, I found no wheel speed sensors, no ABS light, and no toothed rings on the driveaxles. So no ABS. And it's an LS Premium. What the premium stands for is anyone's guess.

2) Release the cruise off button and within 5 seconds press the cruise on button. Now press the remaining buttons in this order. ON, RES, COAST and SET, and ACCEL. As you press the buttons the CRUISE light will flash, Wait till the light goes out to press the next button. After you done doing this test and all the buttons have been pushed the CRUISE light will flash you need to count the flashes.

When I was doing this sequence of instructions I got to thinking. Maybe your only supposed to press the Set/Accel button once.

So the sequence is: hold Off, (turn key to on) Then press "On", "Res", "Coast", then the "Set/Accel" button once each.

Doing it that way, I get 3 flashes. Now here is the caveat. Is it a flash plus 2 flashes to indicate you pressed the correct button, or is it 3 flashes to indicate the unit is flashing 3 times once you press the final button. Pressing the Set/Accel button twice as originally indicated caused the single flash to occur, which may have inadvertently cancelled the self-test.

As far as the throttle opening up, I have not sensed that, since of course the car is essentially off, and you can't really hear it from inside the car.

So anyways I checked around, and 1 flash means nothing except that everything works.

I got 3 flashes, and that is the Brake Deactivation Switch circuitry and the possible cause is a failure of the Brake Pressure Control Valve.

Now before I get to replacing stuff I don't need doing, where is this stuff, and how hard are we talking. The horn works that I know of, and so do the brake lights.

Ok now we are going to do a brake input test to the cruise module.
First disconnect the harness from the cruise servo next to the master cylinder now check for voltage between a good ground and term number 9.
If more then 10 volts then replace the servo as it is bad.
If less then 10 volts then disconnect the deactivate switch at the brake pedal and check for voltage at the light green and red wire and gound (using you multi meter) if less then 10 volts then there is a short in that wire.
If more then 10 volts then check the OHMs of resistance between the tan and orange wire at the brake pedal and the cruise servo term number 9 if less the 5 ohms then replace the brake switch if more 5 ohms then fix the short in the tan and orange wire.
Here is a pic of the cruise control connector so you will know which term number is which. Let me know how it goes.

At the moment it's freezing rain outside, so hanging outside under the hood for the cruise control has had to take a back seat to brake lines that need doing. But I will get back to this this weekend.

Ok that fine. I understand that as we get that here where I live too and it sucks. Get back to me when the weather breaks and you feel like getting back to it and we test the Vehicle Speed Sensor and the cruise servo ok. Thanks again and hear from you later.

I got caught up repairing another car (see questions related to a 1994 Buick LeSabre)

I had to replace practically all the brake lines, all the fuel lines near the fuel filter, and the transmission cooler lines, all the while working in a very cold garage, and trying not to set myself on fire. Add to that, it had this quirk where I had to take it to a garage to use a Tech1 Scan tool to get the air out of the ABS Pump, and the dang bleeder screws/wheel cylinders in the back rusted up.

Fixed that, and low and behold a hole (about the size of my fist -no relation) opened up in the rear tirewell where I replaced all the lines for fuel and brakes. So I'm not just getting back to my original question, and the problem therein. I hope to have some resolution this weekend.

So you managed to get the Cruise Control Self-Test to work then? Which means the light works.

What your problem is, the Cruise light will only come on and stay on, if the system is working. Do the self-test again, in the correct sequence, and tell us how many flashes you get.

So how did it go?

I definitely could've used a helper for this one.

On the Servo check, I could only muster about 1 volt or less, I was never sure it was connected as I had to use a paper clip to slide into the tiny slot of the harness.

So I moved on to the deactivate switch and found that to be at 10.5 volts. Which is good considering there is a break in the wires where I had to replace the old brake switch in order to get the taillights to work, and the Shifter to disengage.

I'm working on the OHM's test. A bit of a challenge as I can't hold the two leads without help, and it's after 9pm.

Ok get back to me when your done that is fine. Did you get to the ohms check? Get back to me.