Electrical issues that are difficult to diagnose—and sometimes intermittent—are typically due to ground wiring issues. The most troublesome ground locations are under the battery or at the engine.Google+
Car Problem Reports
Volkswagen Jetta Difficult to Diagnose Electrical Issues Are Typically Due to Ground Issues
Volkswagen Jetta Problem
Average Mileage: 110,734 mi (17,000 mi - 300,000 mi)
Door locks stop working intermittently. Key always works but alarm doesn't always initiate. Remote for locks doesn't work and it isn't just due to a bad battery. Unlock button on driver's side door needs to be held down forcefully for a long time to get other doors to unlock, sometimes it won't work until the car is turned on. This is driving me crazy!
The main source of my problems was the ground located under the windshield wiper cowling. Remove the cowling and there is a bolt with 3 grounds running to it. Remove and clean the grounds and it should help. I was getting a Cam Sensor Code. Car actually seems to run better too!
Visitor, 1997 Volkswagen Jetta
I have changed the starter and alternator and my car still won't start what else could be the problem
Visitor, 2006 Volkswagen Jetta, 41,000 mi
Light for hood up is staying on, windshield wiper fluid will not spray and wipers sometimes won't work, also having problems with car alarm going off.
Visitor, 2006 Volkswagen Jetta
a/c fan does not come on when a/c is on. both fans have electrical power. also when hooked up direct both fans work
headligh low beam went out . replaced switch. not it. now the lowbeeams on in the DLRunning light position . in the low beab position the headlights work but the dash board doesn't light up. RRRRRRRRRRRRRRR
Visitor, 2006 Volkswagen Jetta, 86,000 mi
Cost me a new fuel line system to realize it was a bad ground and that my fuel line was just fine..
Visitor, 1998 Volkswagen Jetta, 135,014 mi
my windows all quit working, and my abs and cruise dont work as well. im assuming its wiring since they are notorious for the crappy job but i cant diagnose the problems exactly.
Visitor, 1996 Volkswagen Jetta, 175,000 mi
problem with cluster, first erratic speed, gas gauge, no light or gear indicator.
worked ground under battery and sensor, change top sensor under windshiled wipers.
now all work and are right w. But work only intermittently. No answer for that.hen they work
2.5 liter 2005 has had repeated intermittent engine light issues