Glow Plug Light Flashing - Not Brake Switch

benmarks

Veteran Member
Joined
Jun 14, 2003
Location
Portland, OR
TDI
2004 Jetta GLS Sedan Platinum Gray
I have a 2000 Jetta and my glow plug light is flashing. It has been flashing for a while. I took it the the dealer a few months ago and they replaced my brake switch due to the TSB, but no change. I wouldn't let them touch any non-TSB issues. I just had a bunch of other work done here in Portland (a strong recommendation for Fix Um Haus) and they tried multiple brake switches and some other approaches (checked the relay, harness and plugs,) but still no change. I needed the car back before this got resolved, and I know they're still bugged by it, so does anybody else here have any ideas? The error code that keeps re-appearing is for the brake switch. Sometimes after the switch is swapped, the light will stay off for 10 minutes, but it eventually returns and, once it does, it comes on immediately after ignition from that point forward. After performing a search, I noticed a few people resolving this issue by replacing blown tail lightbulbs, but all of mine are working. Could I have put in the wrong bulbs? I haven't found any other causes or solutions.

Any ideas?
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
The first thing that came to mind for me is a loose brake pedal, but I don't know if that would cause this but ask Marcel, it may give him a better idea.
 

AndyhcTDI

Veteran Member
Joined
Feb 10, 2007
Location
salisbury , UK
TDI
mk4 90 tdi
just a an idea but if the brake pressure switch is faulty and reading an incorect pressure the control unit could pick it up as the brake light switch being faulty as the pressure switch is saying the brake is being pressed but the brake swith isnt the ecu will prioratise the brake pressure sender over the switch and come up with the fault being on the brake switch
hope this may shed another angle of diag for you
iv had this prob on a couple of cars now
cheers andy
 

MOGolf

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Jun 27, 2001
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underneath something
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2001 Golf GLS TDI Reflex silver, rough road suspension and steel skid plate, 2004 Passat Variant, Candy White, rough road suspension and geared balanced shaft module, and much, much more. 2016 LR RR HSE TD6, 2019 Jaguar I-PACE
How about getting the fault code from the ECM instead of guessing?
 

Birdman

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Joined
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Location
Near Hagerstown MD.
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Jetta 2001 Died by Truck one snowy day. Jetta 2003
The flashing glow plug is for VW supported items while the check engine is for the Fed OBD items. So a flashing glow plug can and most often is for many other VW codes.
 

benmarks

Veteran Member
Joined
Jun 14, 2003
Location
Portland, OR
TDI
2004 Jetta GLS Sedan Platinum Gray
>> The error code that keeps re-appearing is for the brake switch.

Sorry I didn't give the exact code...

16955/P0571 Brake light switch (F) - implausible signal

Its the same code every time.
 

MOGolf

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Joined
Jun 27, 2001
Location
underneath something
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2001 Golf GLS TDI Reflex silver, rough road suspension and steel skid plate, 2004 Passat Variant, Candy White, rough road suspension and geared balanced shaft module, and much, much more. 2016 LR RR HSE TD6, 2019 Jaguar I-PACE
What color is the switch? Black, purple or green?

There is a possibility that the switch was not properly installed. The non-green ones required the pedal to be held up while installing the switch. The newest ones don't require that.

This is a recalled item on your car. The VW dealership is obligated to replace it and it must work or the recall repair is not satisfied.
 

benmarks

Veteran Member
Joined
Jun 14, 2003
Location
Portland, OR
TDI
2004 Jetta GLS Sedan Platinum Gray
The dealer did replace it once back in the summer, but the light came back. The guys working on my car here in Portland got the most recent switch from the dealer, but still no change... except for the initial delay of about 10 minutes of driving before the light returns.

I'm a bit hesitant returning to any dealer because of my last HORRIBLE experience at Martens in DC. They voided my window regulator warranty due to the fact that I brought my car in mid-speaker install with the interior trim removed and then claimed that I had broken the window regulator because of that.

I'm unsure if the pedal is being lifted (or not) during the install. Just to be sure... is the newest switch green or all black?
 

benmarks

Veteran Member
Joined
Jun 14, 2003
Location
Portland, OR
TDI
2004 Jetta GLS Sedan Platinum Gray
My point by recounting the above story regarding my window regulator experience is that I'm convinced that if I take my car to the dealer, they will argue that the problem is something else purely by default, and I'm trying to figure out if it actually could be anything else.

If the dealer has already replaced the switch once, will they do it again for free? Or, will they begin the process of charging $99 diagnostic fees or recomending something crazy like claiming that all of my wiring needs to be replaced for $10,000?

Also, a previous post mentioned a faulty brake pressure sensor as a possibility. How much would this cost? And, what pressure is it measuring, brake fluid pressure, downward force of foot pressure, etc?

Also, loose pedal... how loose is loose?
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
I'm just taking a wild stab, but maybe it if were loose enough, it wouldn't be possible to install the switch correctly.

Honestly, a Loose brake pedal is something I have never read about here, so it is extremely unlikely. On the other hand, it takes just a second to reach down and check just to be sure. If you can wiggle it and hear it clunk, it's too loose. Otherwise, forget about it and look elsewhere for the problem.
 

MOGolf

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Joined
Jun 27, 2001
Location
underneath something
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2001 Golf GLS TDI Reflex silver, rough road suspension and steel skid plate, 2004 Passat Variant, Candy White, rough road suspension and geared balanced shaft module, and much, much more. 2016 LR RR HSE TD6, 2019 Jaguar I-PACE
There was a second recall due to the high number of incorrectly installed switches during the first recall. Call the local dealer with your VIN and ask if it is covered by an outstanding recall.

Highly unlikely that you'd have a brake pressure sensor go bad without the ABS light on. The only sensor for that would be inside the ABS controller/pump assembly on your car (assuming it isn't retrofit with ESP).
 

AndyhcTDI

Veteran Member
Joined
Feb 10, 2007
Location
salisbury , UK
TDI
mk4 90 tdi
there is a brake pressure sensor on the under side of the master cylinder fitted on cars with esp i have come across it twice now where this has gone faulty but the it brings up a fault with the brake pedle switch first as it see's the brake pedle switch go on but doesnt register any pressure with in the braking system so asums the brake switch is faulty
like i said just another thing to think about , but it had me stumped for a few days as to what the fault was after fitting 3 brake switches to no avail
 

MOGolf

Top Post Dawg
Joined
Jun 27, 2001
Location
underneath something
TDI
2001 Golf GLS TDI Reflex silver, rough road suspension and steel skid plate, 2004 Passat Variant, Candy White, rough road suspension and geared balanced shaft module, and much, much more. 2016 LR RR HSE TD6, 2019 Jaguar I-PACE
A 2000 Jetta in North America is not equipped with ESP unless the owner modified the car (e.g. tongsli).
 
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