99 XC70 Cruise control not working

gerhartj · Post by **gerhartj** » 21 Feb 2008, 05:42

Have a 99 xc70 and the cruise is on the blink. Thought it was the brake pedal switch in that upward pressure from my left foot on the brake pedal would allow me to set it. That wasn't it. Now it is intermitent. Seems like when it s warm it works more often. I had the car raised in the front for a week while I replaced the front O2 sensor (BTW fixes OBD P0422) and it worked first couple times I drove it after I put it back on the road. Other posts discuss vacuum leaks in hoses under the battery tray. not finding those. The 850 criuse control debug procedure discusses parts/points of interest that don't appear to be on my car. Any ideas? Thanks for any help.

Post by **MadeInJapan** » 21 Feb 2008, 07:21

Yes, your car being a '99 won't have the vacuum hoses. Your cruise control is activated differently because it's tied into the ETM someway. Typically, to fix cruise control issues, the dealer will do a software upgrade. However, although I have a '98 with a vacuum hose section, last years, I was also getting intermittent non-working conditions with my cruise control. Like you, I checked the brake pedal and also under the batter. Finally, when I took apart the turning stalk (where the engagement button is) I found a frayed wire that was causing the problem. I reattached the wire and taped it and now I do not have any more problems with my cruise control. It might be a good idea for you also to check where the stalk attaches to the steering column. It is actually very easy to remove to see.

gerhartj · Post by **gerhartj** » 21 Feb 2008, 19:37

Thanks for tip. I'll pull the stalk control apart tomorrow and take a look.

gerhartj · Post by **gerhartj** » 24 Feb 2008, 06:36

Ok, pulled the covers off around the steering column and rolled the rubber boot up the stalk. The wires at that junction look ok.

Couple of questions:
1- Looks like the back of the stalk is made to come apart (little tab you can get a screwdriver under). Thought I might get more visibility to the wires, etc in the stalk but was afraid to force it. Is that made to come apart?

2- There is discission in teh forum about a cruise control module. On my car there are relays/modules above the drivers left foot, beneath the fuse tray under the hood and in the "ancillary" fuse tray next to the master cylinder? Does anybody know where that cruise control module might be? On my Audi that relay needed a periodic reseat (came loose).

Thanks!!

Post by **MadeInJapan** » 24 Feb 2008, 09:58

In regards to the stalk, I don't think the molded plastic part of the stalk comes apart if that's what you're talking about. There are no moving wires in there anyway (minimal chance they would fray or break). If you turn the stalk over, or look at it from the back side, you'll notice 2 gullies (lack of a better term) that the wires are routed into and this makes the wires very stable. Where I saw the break in mine was under the rubber boot where the stalk actually pivots. If no break there and no other place, then it could be one of the switches itself. Btw, if you can't find any solution and you think it's the stalk, I have one off of a late model 850 that I can send you. Wires are cut from the connector to the stalk so you'll have to attach wires to your connector but it should work (assuming all wires are the same: 1. blue 2. red/black 3. white/grey 4. blue/yellow 5. white/black).

That said, the relay in question is under the hood in the relay/fuse box. It is the large one (looks to be the size of 2 relays together) with the numbers 101/102 on it.

Good luck and keep us posted.
-MIJ

P.S. If you want I can take a picture of the spare stalk I have. That way you can confirm it will fit your car. With the confirmation, you might feel better about trying to do surgery on yours, knowing there's a spare to replace it if you damage it beyond repair. If interested, send me an email (badger36 at knology.net).

gerhartj · Post by **gerhartj** » 03 Mar 2008, 14:21

Mystery solved. You were correct in your diagnosis. I just didn't look far enough. I pulled top/bottom plastic covers off of the steering column and removed the stalk from the column (removed 2 torx screws and two plug clips) so I could get it out on the bench and look at it. Red/Black had a decent size break in the insulation. Although, I don't think the wire was broken, I peeled the insulation back a bit, fluxed and soldered the connection and taped it back up. Might have been arcing on the copper or brass arm inside the stalk. Put it back together and

I have consistent cruise again. Thank!!

Post by **MadeInJapan** » 03 Mar 2008, 14:46

Hey, hey hey... Another satisfied customer!

Thanks for posting back and giving closure to your issue.

gerhartj · Post by **gerhartj** » 19 Mar 2008, 17:28

Bummer. Thought I was a satisfied customer. Been messing with this a couple of weeks more. Cruise Control is exhibiting the same behavior. Worked for a couple of days after I fixed the wire. Double checked my wire in the stalk and its is attached and taped. I have been able to pull up on the brake pedal to engage the CC intermitently for the last couple of weeks. Worked this morning then it wouldn't work this afternoon as is typical. Its driving me nuts. No consistent behavior. I'd check the CC relay, but I don't have the modules labeled 101 and 102 in my fuse tray under the hood so I'm not sure where the CC relay is on my car. I did have the "dealer recall" ETM software upgrade done a couple of years ago. Maybe that is suspect. Also about two years ago Victor Rocha rebiult my ABS module, but I'm not sure that has anything to do with CC but I seem to remember CC not working while the module was out of the car. Any help is appreciated.

mishagos · Post by **mishagos** » 16 Nov 2009, 23:22

Yes, me too!