Help with random engine shutoff (electrical)

Jeff7

Well-known member
Joined
Oct 28, 2015
Location
Alberta, Canada
TDI
None
Hey guys, I'm looking for help with trouble shooting what seems to be an electrical problem my jetta has developed, it's a 2009 Jetta TDI 6 speed with about 210km. Recently the engine has started to turn off for no reason, and never consistently. I'll be driving down the road and the engine will just shut off like I turned the key off. Then after that it won't want to start again, turning the key off then on won't make it go through its start up procedure (dash lights come on, all dials go to max then back down, ect). The ignition seems to work, it knows when I put the key in, but basically the car just stays in accessory. Sitting around for a couple minutes and then suddenly it will decide to work and I can start it up no problem. This all happened on the highway, but that's the only place I drive it. It started on a 3 hr drive, about halfway it shut off. The it happened about 6 more times over the course of 30 minutes, just trying to get home. Then the last hour was fine. It was really slushy out so I chalked it up to a wet sensor and didn't drive it for about a month. I took it out today and it happened twice, only about 5 minutes into a drive (3rd start after going to a couple stores in town). I'm not getting any engine lights. I live 3hrs away from the nearest dealer, I know I could get it towed with roadside assistance, but I'd like to sort out myself if I can, I don't want to spend thousands getting a dealer to troubleshoot an intermittent problem. Thanks for any suggestions.
 

Jeff7

Well-known member
Joined
Oct 28, 2015
Location
Alberta, Canada
TDI
None
Not sure if anyone has read this, but I think I might have made a bit of progress. The issue I'm having is the exact same as pulling fuse #2 (dash fuse panel). Unfortunately there's a lot of things on that fuse, so it's possible that it's a coincidence that its the same. On that fuse is: light switch, brake light switch, tiptronic switch, fuel pump (FP) relay, AB's control module, instrument cluster control module, power steering control module, data bus onboard diagnostic interface, and engine control module (ECM).

I'm having a hard time finding anything online, and I'm far away from anyone with a vag-Com. Anyone have input of what I can do next?
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
OBD works, I'd start there. At least it could give you some clues.

Otherwise you can just guess on things. Obviously grounds, underhood fusebox, and the one load reduction relay (I think it is called that, cannot remember) would be my guesses. But I would start by getting a proper scan tool.
 

Jeff7

Well-known member
Joined
Oct 28, 2015
Location
Alberta, Canada
TDI
None
Well I have an OBDII, but no error codes. What else could I use that to look for? And yea unfortunately to get it to a scan tool I'd have to brave a 3 hr drive or pay for a tow.
 

Jeff7

Well-known member
Joined
Oct 28, 2015
Location
Alberta, Canada
TDI
None
Yea that's a possibility... Would you happen to know where the instrument cluster control module is? Everything is pretty tucked away under there and I want to check the wiring to make sure it's all good.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
The Instruments ARE their own control module.

Then there is a Steering Wheel, Gear Selector (if automatic), Central Electronics, Convenience, CAN Gateway, etc.... all of which can be accessed with a proper scan tool. LOTS more than just the engine.
 

Jeff7

Well-known member
Joined
Oct 28, 2015
Location
Alberta, Canada
TDI
None
Ah good to know about the instruments, thanks. And ya I know the scan tool is great, I just bought the car in order to save money on fuel by driving it instead of my truck, so everytime I want to buy something for it I have to remind myself that it's supposed to save me cash and not be a money pit like my pickup haha. Thanks for the help!
 
Top