Cruise Control

[Joeglf4]

I have a general question about my cruise control.....it stopped working not too long ago, and I had asked someone about getting it fixed and was told it could possibly just be a small vaccuum line that may have come off. is this true, and if so is it easy to find? I've got a 2000 Jetta TDI. Thanks!

Joe

[chittychittybangbang]

Possible that a vac line is bad, but I don't think that's the case here. Many gas cars' cruise control work by holding a vacuum against some sort of acuator/solenoid which moves the throttle cable. However, the TDIs are all electronic fueling and no throttle...all the cruise control is is the control stalk, and some switches. The cruise computer is in the car's computer.

First thing to check is theglow plug light. If it's blinking, the brake light switch is bad. This was a recall, it should be green, under the brake pedal. Not green, go get the recall done.

2, might be possible that the clutch or brake switch are faulty or shorted, causing the cruise control to think that the brake or clutch pedal are pressed.

3, also possible that the switch in the column is gummed. Try removing it and cleaning it. If you have a VAG, you can check with this procedure:

Check the switch operation with VAG-COM. ECM measuring blocks group 006. Block 2 leftmost digit is the clutch pedal. Make sure it switches between 1 and 0 as the pedal is operated. The other two digits are the brake switch. Make sure they change too as that pedal is operated.

The left digits of block 3 will also change as you operate the clutch and brake pedals. Operate the switch on the stalk (or steering wheel if equipped) to verify operation by observing the other digits in block 3.

If the switch is bad, here are some instructions I found

On the 1999-2000 models this is a fairly common failure. The ribbon gets bent and looses the connection from the switch to the ECU. The trouble spot is right where the turn signal stalk enters the steering column covers. Putting stress on the ribbon causes it to deflect and twist (such as using the turn signals or high beam switch, etc). It twists in such a way that it will eventually get caught in the seam between the to steering column cover halves. Here it flexes until the wires fail..

The quick and dirty fix is to look behind the turn signal stalk and see if your ribbon is crimped. If it is look below on the easy way to replace the switch. If not, take some electrical tape and cover the seam between the upper and lower steering column covers. Make sure you get the inside as much as possible. This will prevent the ribbon from entering the split and getting crimped.

If your wire is crimped then you need to get a new switch. Recently VW has made a change to the switches. Previously they had one L shaped tab that restricts the movement of the ribbon. The new switches (mine was made in April 2002, old switch was March 2000) have two L tabs to restrict the ribbons movement. This is clearly a design change made solely to prevent the ribbon from failing.

I feel VW should replace the old failed switches free of charge. I'm not the only one who's had this problem, and they've clearly made a design change to correct the switch. (where's my digital camera..) Interestingly enough, they just massively dropped the price of these switches. I got mine for $64. They used to be $140 or so.. Seems almost like the MAF pricing to me..

To replace the switch you do the following (mainly out of the Bentley book):

1. Disconnect the Battery. Airbags are not fun to play with while they are "live"..
2. Insert a flat blade short (less than 6" ) screwdriver into the slots located on the back of the steering wheel ( ~ 3 o'clock and 9 o'clock, you'll have to do one side, turn the wheel and then the other). Pry from the outside to the inside to release the airbag clips. Remove the airbag.
3. Use a 12mm triple square internal socket to remove the steering wheel. Important: Mark where the wheel is centered.
4. Undo screws on the lower and upper covers. Move out of way. (4 small Phillips and one Torx)
5. Remove clips on centering ring. Remove.
6. Loosen bolt behind switch cluster (5mm Allen, on top). Remove connector (4), and remove switch assembly.

Now the tricky part. Look the switch assembly over, it's in 2 halves and a bear to get apart.. Until you undo the center clip ( ~ 3 o'clock) and it slides right apart. DO NOT PRY ON THE EARS UNDERNEATH THE SWITCHES.... don't do it.. Trust me..

Installation is reverse of dis-assembly. Make sure the centering clip rotates freely, mine clicked while turning after re-installing it. Had to remove it a and re-install it again.

Total time: 1.5 hours (first time)

[jon applespeed]

The main thing to look out for is if anything else has a problem. Try to group a number of symptoms under 1 diagnosis. And it helps if you go from easy-hard.

If the glow plug light is on, the brake switch is suspect.

If not, then check the brake switch and cruise control switch for wiring and operation.

If not, then check the cruise control switch.

IYou could have a bad vaccum line but i don't think it's relted to the cruise control issue.

And if you still have a prob, it could be related to the ECM or wiring.

[luke33]

I thought that the vac lines needed replacement every so often?

[chittychittybangbang]

Originally Posted by luke33

I thought that the vac lines needed replacement every so often?

yes, but it's not related to the cruise control system in these cars.

Many gas cars and non vws have cruise control systems or separate computers and solenoids for the cruise control. These cars have no throttle to control.

[TDI2000Zim]

I lost my Cruise three years ago, and I thought it was only me.

Lots of heartbreak.

[El Pozero]

I also have CC problems. If it is the Cc stalk will all the other functions work properly? I have read there is a relay for the CC, can someone tell me which one it is?