Cruise control not working

I purcahsed a used 1999.5 Mk4 TDI Jetta a little while ago. The cruise control doesn't work on it yet all the vacuum hoses seem to be good. Any suggestions of what to try to diagnose the problem. There is no message from the OBD. Does anyone know what fuse the cruise control works off of?

Thanks in advance.

I don't remember the fuse number but it is shared with other items in the interior controls. It could be one of two switches, brake or clutch or the CC switch itself that have gone bad. It could be turned off and you need to confirm with VAG that it is indeed enabled. I have the same problem only more mysterious in that the VAG tests on the switches all pass fine, it is turned on, fuse is good...still no cruise. So, I live with it but I don't do many long trips that would make it nice to have, again.

Check
1. brake light bulb
OR
2. brake light switch

Do a search for cruise control and flashing glow plug, you will see lots of post on this issue.

I used my turn signals so much that the cruise stopped working. There is a ribbon cable that runs out to the stalk switch that wore through. But I knew the problem was there as it would work until I signaled right, then I would have to re-engage.
Didn't think a TDI used vacuum for cruise. My 99 NB doesn't.
The switch cost me $65 from VW. I may repair the old one later.
Brad
If you just gyou

Change the fuse regardless, my didnt look blown but it was.

I've had a couple instances where my cruise quit - what I did was to stop, shut down for a few minutes, and get going again. I've found this effectively "reboots" the cruise and it works again on the restart.

Brake light switch.

I just pulled the brake switch from my mother's passat, disassembled it, cleaned the carbon from the contacts, and reinstalled it. She had intermittent cruise failure until one day she had absolutely no brake lights at all. It only takes a few minutes to do, and may prevent you from buying unnecessary parts.

My cruise quit a couple of times too. It seemed to happen when I was hitting resume at low speed and the auto trans was searching for a gear. Any way the criuse quit and would not work untill I slowed to a stop. I did not have shut off the car to the cruise up and running again. It has done this 4 times now and each time I slowed to a stop, and it reset. I was thinking some how the vehicle speed sensor was messing with the cruise control. By slowing down it reset something or another.

My 01 golf cruise quit and the dealer replaced the cruise control switch to make it work.

The contacts in the brake switch arc. This causes carbon to build up. In many cases, pressing on the brake pedal will move the contact just enough to allow current to flow again. That's why slowing to a stop sometimes works. Kicking under the left side of the dash might work just as well, but I'd pull the brake switch and clean it.