matt_o_70

Hi all
2004 S new to me.. the only issue (so far I am aware of) is my cruise control will not turn on. I have pulled the lever toward me, and it clicks into this position. but the ready light on the dash never illuminates and trying to set a speed I get nothing.

So I am looking for any collective wisdom or past experience on this issue? I am off to try to locate the fuse panel to check it... no codes stored according to OBDII

Andy E.

Your brake pedal-activated switch may be defective. Apparently, this was a common issue on '04 M.Y. Cayennes.

Slow Guy

There are 2 fuse panels, 1 on each side of the dash, only accessible with the doors open. IIRC also a relay panel under the hood up next to the front windshield, driver's side. Owner's manual should tell you which one it's in.

I've not had to do any work on the Cayenne cruise control but fuse/relay would be the first thing I'd check based on your description.

mikeymike79

My green "cruise control readiness" light never goes off. Is it actually always supposed to stay on?

99firehawk

If the brake light is bad the truck will start without pressing the brake, if your not getting the green light its not a brake light switch. your going to need to do some real diag andit would be tough without a tester.

matt_o_70

Anyone have wiring diagram and know if contacts are unique for cruise control? There are 4 contacts in the brake switch. My brake light works and the car wont start without depressing the brake. But simple continuity test only added to confusion. Across contacts 2&3 it was not showing open/close asone might expect - it was behaving like a variable resistor as I pushed the plunger. So before I go farther and make any assumptions - I'd like to better understand the system. Has anyone been here before and can confirm that brake switch center contact should be open and close and nothing else?

contact 1 & 4 did not give any readings when tried with any combination of alternate contacts. I'll go see how cheap or expensive the part is..

grohgreg

A loose filament in a brake light bulb can fool the cruise module into believing the brakes are being applied, even though it may not even be illuminated. Change both brake light lamps and see if the problem persists.

//greg//

99firehawk

If you removed the brake light switchfromthe horse shoe bracket its garbage now, they are one time use . But the green light has nothing to do with the brake light switch, my guess would some one (dealer) programed the car incorrectly and the coding is off. And btw a loose filiment will not make a cayenne think the brakes are applied.

grohgreg

I'd be interested in the rationale behind that statement. I wouldn't have mentioned it if this vehicle had LED brake lights. But the older Cayennes use incandescent brake lamps just like one of my Mercedes. I wasted money on a new module that didn't fix the problem of my cruise control arbitrarily shutting itself down. Both brake lights appeared to be working normally, so I didn't think about changing bulbs at the time. After spending big bucks on what turned out to be an unneeded cruise control module - the problem was ultimately fixed with one 85 cent brake lamp

//greg//

TozoM8

Loose bulbs can cause a lot of trouble. I've seen a short in the socket telling the TCU that the brake is pressed all the time and the torque converter stayed open burning up the transfluid.

matt_o_70

I have ordered a new brake switch it's only $10 online..

I see what you mean about the one time use.. http://forums.vwvortex.com/showthread.php?1158315 there seems to be quite a bit of chatter about it and multiple recalls on the VW part.

when I asked at my local dealer about a replacement - the counter guy could not find a part number that was in stock anywhere in the USA - I think he must have been looking at older part numbers... hard to believe there are ZERO in stock in USA.

will the Durametric enthusiast package - allow visability into the status / programming of the cruise control?

99firehawk

I had to think long and hard about how a loose filiment could cause a car to think the brakes were pressed, The best idea I can come up with is with the running lights on the running light filiment shorts to thebrake light filiment and energizes the system, this would provide power to bulb (they would light up, both sides if they share a power circut) and it could then send a voltage signal to what ever controls the cruise control to think the brakes were appplied. Im guessing this was a early car something that you could take a bulb out of and not get a warning on the dash.
Cayennes are smart, too smart for their own good, even the early ones, plug a trailer into one with led lights or the wrong number of filiment bulbs. Any bulb out or added to a cayenne causes an error message.

A short in the socket, same deal im guessing this was on something old, surely wasnt on a cayenne.

Either way we are not talking about a cruise cancel problem the problem is the cruise never turns on to the point it can be activated. The green light should turn on with the brake pedal pressed so that rules out the brake pedal aspect. U have either a bad signal from the steering colum switch or the dme is coded to have no cruise or some one coded it to be a 2005 or newer cayenne and the only side effect of doing that is the car has a diffent brake switch system and you loose complete function of the cruise control. A 2004 cayenne problay got the coils replaced under the extra warranty and with that they should have reprogramed the dme, easy mistake ive seen it happen twice.

I dont know about he durametric, im going to say no

ryan19

Have that issue also. Checked the cc switch with scanner and all functions show good. Brake lights work also the switch works. Green light on dash works. Is there a way to set cruise control on in the programing without Porsche scan tool? Its all I can think of why it won't work.

m a x i m u s

Has it never worked for as long as you've owned the car? Does the car have non-stock sized wheels/tires on one of the axles? Sometimes that will confuse the computer and the cruise will not work.