Intermittent Cruise Control
23rd November 2012
My VW Golf has had the common Mk 5 problem with an intermittent cruise control for many years now. VCDS reports:
"18104 - Powertrain Data Bus
P1696 - 000 - Implausible Message from Steering Column Controller - Intermittent"
It never knocks off whilst it is actually maintaining a set speed but occasionally, when you attempt to set a speed, it will not and looking at the dash you will see that the cruise control warning light has gone out. You have to turn the ignition off (with the car stopped obviously) and on again before it will work again.
I had heard that the problem was faulty contacts in the control stalk and that the official repair from VW is to fit a new stalk costing approximately £120. However, I found an article online which suggested that this problem could be fixed simply by removing the cruise control switch module from the stalk (without needing to remove the stalk), giving the contacts a clean and refitting.
For a long time this problem didn't seem to occur that often in my car so I never worried too much about fixing it. However, recently I found the problem becoming more frequent and decided to give cleaning the switch contacts a go.
Cleaning the switch contacts
Gaining access to the cruise control switch module was easy. The back of the stalk just pops off and the switch module with about 6 inch long lengths of wire attached can be extracted quite easily to gain better access.
However, unlike in the Danish article where the switch module can be unplugged from the wires, I found that on my Mk V the wires were soldered directly onto the module's circuit board. VW must have changed the design slightly.
With the switch module accessible it was easy to see how it was assembled. Two crosshead screws (not torq screws like in the Danish guide) held the switch mounting to the circuit board. The circuit board contained the contact area for the cruise control's ON OFF rotary switch. Two microswitches fixed to the left hand side of the circuit board are pressed by the SET RESUME rocker switch on the end of the stalk.
Removing switch mounting showing 2 microswitches
and rotary switch contact area on circuit board.
Click on photo to enlarge.
I couldn't see an obvious way of cleaning the contacts of the microswitches so I didn't do anything to them but cleaning the contact area for the rotary switch was easy. I used a cotton bud dipped into a little white spirit and after use it looked to have picked up quite a bit of dirt.
Reassembly and refitting was easy enough. All done within 30 minutes.
Update: 16st October 2013: Nearly a year later and my car's cruise control has worked perfectly ever since! Also, a lot of people have contacted me saying they have also got their cruise control working again after cleaning the switch contacts. Looks like a common problem but also, an easily fixed problem.
Update: 2nd December 2015: I think it was sometime this summer when my car's cruise control starting turning itself off again. I lived with it for a while but it was becoming progressively more freuquent so I gave the switch contacts another clean. Problem solved... again!
Miscellaneous
Owners' experiences of this solution can be found on BRISKODA.net.