Glow Plug dash light is flashing

OmahaTDI

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Joined
Apr 6, 2012
Location
Nebraska
TDI
2005 NB TDI 5-speed
The NB was fine this weekend & today. She fired and drove without issue getting us home safe and sound tonight. I went out just now to go to the store and I start it and it dies after ignition. The glow plug dash light is flashing now.

I replaced the battery with an OEM replacement last Friday and it was fine all weekend and today.

Any ideas what's causing this?

Thanks in advance

-Bob
 
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Seatman

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Apr 23, 2010
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Scotland
TDI
2007 Seat Alhambra 2L tdi
There's a list of possibilities around here but not sure where, sounds like it's not the brake lights in your case though or the tps, could be the #3 lift sensor on the 3rd injector. You'll probably need vagcom to get to the bottom of it though.
 

CopaMundial

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Jan 30, 2011
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Southeastern PA
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03 Jetta Wagon 5sp (New to me Oct 2014) 03 Jetta 5sp (RIP Aug 2014)
The flashing glow plug light is another variety of check engine light. It doesn't necessarily relate to the glow plugs themselves at all. They use the check engine light typically to indicate issues that will impact emissions. Flashing glow plug light is for a collection of things that require attention but do not affect emissions.

The best thing to do is to scan the diagnostic codes.
Here are some possible causes of flashing glow plug light as assembled by MoGolf.
http://forums.tdiclub.com/showthread.php?t=67848

As Seatman mentioned having two brakelights out, or the brake switch out will cause the flashing glow plug... but it will not cause the car to stall after starting.
You will have some code stored. Need to scan it to read that code.
 

RacerTodd

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Jun 28, 2007
Location
Kirkland, WA
TDI
2001 Golf TDI
Four times so far, about every 18 months, I will start my car and get the flashing glow plug light. Car runs and drives normally. Turning ignition off and restarting turns the light out. All four times, no codes were stored.

If it does this once and doesn't come back, don't sweat it. I think my ECU is a drama queen and just needs some attention once and a while :D
 

CopaMundial

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Southeastern PA
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03 Jetta Wagon 5sp (New to me Oct 2014) 03 Jetta 5sp (RIP Aug 2014)
If it does this once and doesn't come back, don't sweat it. I think my ECU is a drama queen and just needs some attention once and a while :D
In your example I would agree, but the OP said that in this case the engine dies.
 

OmahaTDI

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Apr 6, 2012
Location
Nebraska
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2005 NB TDI 5-speed
I've read that it may have something to do with the brake switch. I checked last night and my brake lights are working. I'll have to order a scanner.

How can I pull a code if it won't stay running?
 

fruitcakesa

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Feb 18, 2007
Location
Vermont
TDI
04 jetta 5 spd wagon
I've read that it may have something to do with the brake switch. I checked last night and my brake lights are working. I'll have to order a scanner.

How can I pull a code if it won't stay running?
The code is stored. You can read it with the scanner.
 

RacerTodd

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Joined
Jun 28, 2007
Location
Kirkland, WA
TDI
2001 Golf TDI
I've read that it may have something to do with the brake switch. I checked last night and my brake lights are working. I'll have to order a scanner.

How can I pull a code if it won't stay running?
Note the brake light switch actually has two switches inside. One runs the brake lights, one reports to the ECU. Just because the brake lights work doesn't mean the other switch isn't causing problems.

Codes are read with the ignition on. Car doesn't have to be running.
 

Vince Waldon

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Joined
Apr 25, 2009
Location
Edmonton AB Canada
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2001 ALH Jetta, 2005 BEW Wagon
My internet guess, since the engine dies soon after you start is, is a code along the lines of "QA lower (or upper) limit exceeded"... meeting your pump's Quantity Adjuster has worn, is dirty, or otherwise misbehaving.

But yup.. get 'er scanned. The car knows what is wrong and is trying to tell you. :):)
 

dogdots

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Sep 4, 2002
Location
Kansas City
TDI
None
OP has a BEW not an ALH so no lift sensor and no rotary injection pump. Gotta scan it for codes for troubleshooting.
 

OmahaTDI

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Apr 6, 2012
Location
Nebraska
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2005 NB TDI 5-speed
Follow-Up

I borrowed a scanner from a friend and connected it with the key on. It came back "No Codes Present". So I disconnected and reconnected and got the same reading. Seemed weird but it still wouldn't stay running & the glow plug dash light still was flashing away. The only thing that had changed shortly before I had the problem was I changed the battery. I popped the bonnet, to check the connections and all was well.
So I decided to do what I do to my work computer when it acts up & "reboot it".
I disconnected the positive battery cable, waited 30 seconds and reconnected it. Jumped in the car and it fired right up and no more flashing glow plug dash light. Drove it around the block and it was fine. Shut it off in the garage & fired it back up - no problems.
Hopefully it was something as simple as that - but who knows?
Thank for all the help and, at least I have my own scanner ordered ;)
 

Vince Waldon

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Edmonton AB Canada
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2001 ALH Jetta, 2005 BEW Wagon
Darned Tapatalk doesn't show me stats...sorry for the confusion OP.

My guess is that your friend had a generic OBD2 scanner? If so that might explain why no codes were found, and hopefully the scanner you have on order is VCDS. :)

Sent from my Nexus 7 using Tapatalk
 

OmahaTDI

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Apr 6, 2012
Location
Nebraska
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2005 NB TDI 5-speed
Yes, dognots, that is the one I should get instead. I've requested a cancellation on the one ordered on Amazon so we'll see.

I stopped by my buddy's shop. He has the VCDS from Ross-Tech. We plugged it in and it showed 2 faults:
19463 - Camshaft Position Senor (G40)
17978 - Engine start blocked by immobilizer

He said that sometimes these codes are due to a bad brake switch, as some of my research has shown. They're going to give me a call and I can bring it in then to root out the problem.
 
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Vince Waldon

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Joined
Apr 25, 2009
Location
Edmonton AB Canada
TDI
2001 ALH Jetta, 2005 BEW Wagon
The flashing glow plug light can be caused by a bad brake light switch; those codes are caused by issues with those specific systems. :)
 

CopaMundial

Veteran Member
Joined
Jan 30, 2011
Location
Southeastern PA
TDI
03 Jetta Wagon 5sp (New to me Oct 2014) 03 Jetta 5sp (RIP Aug 2014)
I stopped by my buddy's shop. He has the VCDS from Ross-Tech. We plugged it in and it showed 2 faults:
19463 - Camshaft Position Senor (G40)
17978 - Engine start blocked by immobilizer
Do you get the immobilizer indication on the dash? Yellow car shaped symbol with a key at the bottom?

 

Vince Waldon

Top Post Dawg
Joined
Apr 25, 2009
Location
Edmonton AB Canada
TDI
2001 ALH Jetta, 2005 BEW Wagon
This is one of the (many) times we could wish that the ECU had a real-time-clock, so that it could time-stamp the error codes.

Meaning, the immobilizer code could be recent (in which case the light should also be on, as the helpful picture above indicates) but it could also be an old code from a long time ago that was just a fluke one day when the key and the pickup didn't quite get along for the first twist of the key.

Now that the codes are recorded it might make sense to clear 'em and see what comes back.

Having said that, of your two codes listed only the crank sensor one would flash the glow plug light... immobilizer issues only flash the immobilizer light, IIRC.
 
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