My instrument panel lights flicker when it's cold

gmiller

New member
Joined
Dec 9, 2005
Location
Staunton, VA
TDI
2005 Jetta wagon TDI
When it's about 40 degrees F or colder, my instrument panel lights flicker. The VW dealer says it's because power is going to so many different systems--seat heaters, head lights, etc.--and the flickering is happening when the glow plugs kick in, as part of normal "electrical draw". This answer seems stupid to me--flickering lights aren't normal! Does anyone else out there have a TDI that does this? What can I do?
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
I think he's partially correct, but I'd clean the contacts of all of the grounds you can find - and you'll find a few under the battery. Corroded grounds cause issues when the power available is overcoming various pieces of electrical equipment AND being interferred from completing the circuit by some corrosion. You may not notice it in warmer weather, but with increased draw on the battery, it rears its ugly head. Only to get uglier as the corrosion increases, causing such problems as loosing your trip meter and clock when you turn the key.

That's my guess.
 

sootwagen

Veteran Member
Joined
May 25, 2003
Location
Nowhere
TDI
None
My 2003 Jetta wagon had a bad ground under the dash board repaired under warranty for this problem. When I would make a turn, the dashboard lights would go out, and then come back on. Additionally, if I was going down the highway with the cruise control engaged, and I put the wipers on intermittent setting, the cruise control would occasionally disengage when the wipers kicked on. This problem also went away after the repair.

Lights may dim slightly when a large load kicks on, but they shouldn't *flicker*.....
 

Zero10

Veteran Member
Joined
Jan 16, 2004
Location
Calgary, AB
TDI
05 Golf TDI PD, Tiptronic
My 05 golf does the same, when it's about 5*C and below (roughly the same temps as you). Except on mine, all the lights in the door go out for a second or so, the dash lights will go right out for a split second, etc. You can sit and watch the radio light flicker. Bringing the revs up to 2000RPM or so doesn't make it go away, so I doubt it's the excessive electrical load, unless these things are built to draw more than the alternator can put out when they're cold (which would be a bad idea). If I turn my heated seats, rear defrost, etc. off it makes no difference.
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
Metal shrinks when cold, so it could be a plug, poorly soldered wire, or a broken wire that connects in higher temps. I'd bet on a 2005 as having a plug that's not really tight. Very small bet, however.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
Let me guess, the lights filckered around 2400 RPM?

The glow plugs run after the engine is started, until the temp gague begins to move, when the engine is below 2400 RPM. When you go above that rpm, they click off, and when you come back below it, they click back on, and the inrush draw makes the lights dim.

Now, if it is flickering all the time, then you are having an eletrical problem...

-J
 

PDJetta

Top Post Dawg
Joined
Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
The panel lights in the '04 flicker slightly after I start it and for a couple (few) minutes afterwards. I'm curious too. It appears to happen only when its real cold out, so I would guess the flickering is caused by either the engine and/or coolant glow plugs being modulated by their controller. That's my guess.

--Nate
 

Zero10

Veteran Member
Joined
Jan 16, 2004
Location
Calgary, AB
TDI
05 Golf TDI PD, Tiptronic
In my case, it happens at idle, at 1000rpm, at whatever rpm, it's constant, and independant of engine speed. I talked to the dealership, and they pretty much told me 'tough luck', if I leave it there for a whole day they can try and find it, otherwise I have to live with it. I don't trust them with my car, they have proved to me many times why I should not... I don't know what to do, but I would like to fix it myself.
Although I cannot speak for the original poster, and I hope I haven't hijacked this too much.
 

snoopis

Veteran Member
Joined
Aug 18, 2002
Location
Arlington, TX, USA
TDI
2002 Golf GLS TDI, 5spd
I used to have some flickering/dimming like this, but never thought much of it. Then one day my brake/ABS lights started flashing and beeping at me. After searching here, I figured it was the ground under the battery, so I cleaned that up- not only did it solve the brake/ABS issues, but the flickering was gone too. :)
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
If you rule out a loose ground replace the headlight switch. If you have outside lights and no dash lights intermitently it's a bad switch. Fixed another tonight.
 

supton

Top Post Dawg
Joined
May 25, 2004
Location
Central NH (USA)
TDI
'04 Jetta Wagon GLS
My '04 does the same--not only that, but I'm getting RFI on a UHF frequency. The other day, turning the lights off and on fixed the RFI, the following day it was turning the heated mirrors off and on, and then today nothing worked to fix the RFI. Didn't look to see if the dash lights were flickering, but I have seen it in the past month, so I know it's there.

Under the battery, you say? Any other problem areas to be checked too?
 

PDJetta

Top Post Dawg
Joined
Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
I swear, its gotta be the glow plugs (coolant and/or engine GPs) cycling, drawing power, causing the flicker. I do not notice the flicker when the engine is warm. Only for a few minutes when its cold.

--Nate
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
PDJetta said:
I swear, its gotta be the glow plugs (coolant and/or engine GPs) cycling, drawing power, causing the flicker. I do not notice the flicker when the engine is warm. Only for a few minutes when its cold.

--Nate
Flicker is one thing. Lights going out it another. Your flicker is the sign of a battery needing charging. Your GP's draw some SERIOUS Amps.
 

Zero10

Veteran Member
Joined
Jan 16, 2004
Location
Calgary, AB
TDI
05 Golf TDI PD, Tiptronic
The glow plugs cycling shouldn't cause the lights to flicker at between 1-30Hz, mine flicker pretty much randomly, sometimes very quickly (fast enough to be really distracting), sometimes very slowly, or not at all.
Turning on/off electrical devices doesn't change it, same with revving the engine. I think it might be the light switch. I tried turning them off and back on and that didn't cure it, but maybe the switch is dirty inside, or there is some frost inside it or something.
 

FourBanger

Veteran Member
Joined
Oct 6, 2005
Location
Toronto, Canada
TDI
2003 Jetta GLS, Reflex Silver
My radio display flickers every so slightly, almost not noticeable, when there the car is cold and I have the headlights and heated seats on. The rest of the dash lights and gauges do not flicker. It goes away once the car is warmed up.

Unless yours is really really noticeable it's probably normal.
 

Zero10

Veteran Member
Joined
Jan 16, 2004
Location
Calgary, AB
TDI
05 Golf TDI PD, Tiptronic
Mine causes all of the interior lights to go out for a second or two at a time, it's really really noticeable.
 

fitzski

Veteran Member
Joined
Oct 13, 2004
Location
Ottawa
TDI
Uh... hmm... Well, none...
FourBanger said:
My radio display flickers every so slightly, almost not noticeable, when there the car is cold and I have the headlights and heated seats on. The rest of the dash lights and gauges do not flicker. It goes away once the car is warmed up.

Unless yours is really really noticeable it's probably normal.
Mine, 2004 PD, is exactly the same - just the radio display, and barely noticeable at that.
 

rah7777777

Well-known member
Joined
Sep 25, 2005
Location
texas
TDI
2011 Jetta SportWagen TDI
on mine when its cold, the headlights will flicker for a few minutes, looks like im flashing people as its a big difference, and when it does it i can hear a relay in the dash clicking too, a few times the cluster would flicker too. seems as if i use my zerostart coolant heater it doesnt happen on start ups often. but sometimes after even a 30 mile highway drive when i get off the highway it will start up again, im thinking i need a new battery. as when i tested with midtronics it failed. hopefully that fixes her.
 

DieselFumes

Veteran Member
Joined
Oct 18, 2002
Location
Greenwood, IN
TDI
2002 Jetta TDI
Have you replaced your battery recently? I had a battery replaced on a Saturn wagon and the lights flickered afterwards. Turned out it was a bad battery.
 

Zero10

Veteran Member
Joined
Jan 16, 2004
Location
Calgary, AB
TDI
05 Golf TDI PD, Tiptronic
Also curious. It's been cold again lately, and this is getting excessive. I had my instrument panel lights go out for ~2 seconds while I was driving at night.
I'm lucky I haven't lost my headlights yet.

I don't think it's the alternator, since the headlights don't noticeably dim when this happens.
 

jpego1

Member
Joined
Jan 9, 2006
Location
New Jersey
TDI
99 A4 Jetta
Hello, I have the same problem, when its really cold (20’) the dash & headlights dim (basically everything electrical), you can hear some clicking noises coming from underneath the dash, but this morning the car actually cut off on me & I needed to get a booster to start the car. What I don’t understand about this problem is that once the car restarts everything goes back to normal & leaves no evidence of a problem. Could it be a relay? Good to know I am not alone here. Thanks.
 
Top