Please help -tdi glow plugs

My girlfriend just bought my grandparents 2000 vw beetle which is a diesel. The check engine light came on (i know she has accidently tried to start it without the glow plugs being warm) and we had the code read and it said it was a glow plug circuit failure and malfunction. She can start the car and leave it in park without the check engine light coming on, however if she puts it in drive or reverse the light comes on. So my question is what could be causing this because it starts and runs fine, and what can be done to test/fix it? We live in utah and it has been in the teens and 20's so it has been really cold.
Thank you,
Patrick

ok
i had the same problem when i bought my tdi
glowplugs just get it started they are not needed to run engine so you are fine.
To fix your problem you either need to 1) replace glow plugs/ harness (unlikely) or 2) you have a connection problem like i did, go to lowes homedepot or some hardware store and get yourself some Ox-Guard stuff for like 2 or 3 bucks, pull off harness and put a goober of the stuff on the end of the 4 plugs and clear the code and you should b good to go.
WORST case is youd buy a $60 set of glowplugs and/or a $20 harness
good luck
edit: ox guards rated flashpoint is like 1400 degrees F so it is totaly safe to use on your engine wiring components, you exhaust mani shouldnt even get that hot.
re edit: dont let the stealership bend you over for some lame repair cost

do you play diablo2? if you do im on east ladder, my account is sinoflife if you wanna chill sumtime

Hmm ok thanks..... one problem, i have never touched a diesel engine in my life, so where how and how much? I usta play, but havent in a long long time

glow plugs

When you look at the front of your engine near the top there is a black harness about the thickness of a pencil that has 4 vertical connectors - sort of like "mini" sparkplug connectors.

Here is a closeup of the cylinder head with both the fuel injectors ( they have metal lines screwed into their tops ) and glow plug harness ( black rubber rod with little "tees" coming down off of the main link ).

The second photo is a shot of an engine bay to give perspective. And once again the glow plug harness is the horizontal black tube in the middle. The photos are not of the same engine.

here are the connections you need to pop off, just use firm steady pressure to pop them off they will click and unclick just like sparkplugs.

Here's everything you ever wanted to know about the glow plugs and how to fix them. http://forums.tdiclub.com/showthread.php?t=79819