Intermittent Cruise Control

[Carbonics]

93 civic 175k, the cruise control only works sometimes and it's irritating me.

on the left side of the panel behind the steering wheel is a cruise control button, you push it and it lights up green - meaning you can use CC now.

then on the steering wheel you set cruise control, but it only works sometimes, then when it does work it kicks off most of the time.

any ideas? thanks.

 

[porcupine73]

Is there some kind of switch for the thing on the brake pedal? If so maybe it's out of adjustment or something. Usually these things are 'fail safe' so if the switch is bad or a connection is bad it kicks off (rather than loose the connection to the switch and then won't switch off when brake it pressed)?

 

[Gary Allan]

Does it resume when you hit the RESUME button?

 

[Carbonics]

no, cause if you press both the res/accelerate and cruise buttons it cancels it out and I do that before trying to get it going, it's weird, I thought it might be a fuse but then it wouldn't work at all if that was the case. Must be the electrical, car is 13 years old.

 

[Gary Allan]

I'll go for corrosion at the switch contact points. I'd try some type of safe electrical cleaner to see if dust and/or whatnot is bridging the contacts.

 

[Tosh]

In addition to the lighted CC switch, isn't there also a green 'cruise on' indicator in the instrument panel? Does this light also go out when the cruise disengages itself? Perhaps the vacuum-driven throttle actuator is weak? But first rule out the switch at the brake pedal.

 

[Carbonics]

yes theres the CC switch, then when you activate it on the steering wheel it lights up green on the instrument panel, sometimes it does and it starts working then it will kick off.... I did have it going for 6 miles once last week driving to San Diego but had to tap the brake cause of traffic.

I'll have to check out the brake pedal switch, what should I look for exactly? thanks guys.

 

[Jim 5]

I think porkupine hit the nail on the head. I'm told that the most common reason for failing cruise control systems is a faulty brake switch.

All cruise controls have a normally closed switch that gives the cruise unit power when the brakes aren't activated. This is typically a dual switch (on side for brake lights and one side for cruise).

When this switch gets worn it will cause intermittent failures on your cruise control system. The exact same thing as you described happened to me on my '98 chev K1500.

It makes sense that this would be the most common failure point on a cruise system, if you consider how many duty cycles a brake pedal switch is going to see over the life of the car. This switch will be most often used/moved part in your cruise system, and should logically be the first part to wear out.

Check at the very top of your brake pedal under the dash. Usually there will be a switch with around 4 wires going into it there. That switch is activated every time you hit the brakes.

Let us know how it works out. I'm guessing this is most likely your problem.

 

[dwendt44]

To add to what Jim said, as the brake pads wear down the brake pedal will sometimes 'sag' a little, just enough to put the switch at the point where it's on sometimes and off sometimes.
Had the same problem with a Chevy truck once.
a slight adjustment and the CC worked like new again.

 

[OBIO3]

It's possible the brake switch got out of adjustment after 13 years but most likely it's shot. Mine kicked out at every bump in the road.At times it took 50 or more miles to get it to work again . I just got a replacement at a junk yard for 2 bucks and it works perfect.