Blue Coolant Warning Light

[kalooki]

2001 New Beetle 2.0, 30k miles, I've only had it a couple of months.

Since I bought it, the blue coolant warning light has come on at startup, then eventually has turned off. Having read this and other forums I believe this is normal enough behaviour.

However, it seems recently that the time to turn off has been longer and longer, and today for the first time after about 15 minutes of stop/go traffic the light started blinking blue.

Uh oh. Kept driving to my destination planning to get coolant etc etc but then after about five mins it goes out again. Phew (I hope). Popped the hood after I parked and the coolant tank looks very full (hard to see the marks tho) but that's probably because the engine was still warm.

Coolant is nice and red so it looks like the previous owner used the good stuff.

The only other problem experienced with this car is that on 2 occassionas it has required 2 or 3 goes to start. Normally perfect.

Other info; I'm currently getting about 320 miles per tank.

QUESTION: Have I a problem with the coolant itself, the tank, the sensor? What does the flashing blue light really mean?

Help appreciated.

[ubugnme04]

The blue light normally indicates that the engine is cold and will go out after it warms. I am not sure why it would blink while blue. Sorry I couldn't be more help.

[Bob]

I can't say I have an answer for you either, but weirdly enough, just last night I was in a bit of a rush about 100mph *cough* and my blue coolant light came on in the middle of the trip for no apparent reason. Then it went back to normal. Maybe it's just their time of the month?

[D2Beetle]

According to my '98 Owners Manual if the Blue Light is on at any other time other than warm up, it is an indication that the cooling system is experiencing an "electrical problem"; it is not specific as to what the electrical problem could be.

[LadybugEwa]

I'd suspect the coolant sensor or the thermostat.

[05yellowbeetle]

The thermostat does not have anything electrical attached to it, plus my '98 was without a thermostat for about 3-4 months after I bought it and it never had a warning light on. I would replace the coolant sensor. I remember reading others had that issue and that was the culprit.

[HarlequinPixie]

Originally Posted by D2Beetle

According to my '98 Owners Manual if the Blue Light is on at any other time other than warm up, it is an indication that the cooling system is experiencing an "electrical problem"; it is not specific as to what the electrical problem could be.

My little blue thermometer light has been going off and on all the time I'm driving for the last week or so, too...

Bleh. been meaning to get out the owner's manual to see if it said anything about it coming on at any time other than startup (already knew what that meant), but haven't had the chance. Guess that since I didn't drive it to work today I'll take a look at the coolant level when I get home, then bust the book out. Probably a good thing I was planning on taking it in to the dealer next week for an oil change (it's free, otherwise i'd go somewhere else, etc).

[wawalker]

coolant sensor.

[red5]

when it flashes blue, it is a P0116 problem on the OBDII scan. it means that "the engine coolant temperature circuit have a range or performance problem" in clear, it means that the engine coolant temperature sensor senses engine coolant temperature. The ECM uses this information to control fuel injection duration and ignition timming. So, if it flashes blue, it only means that the information send to the ECM is incorrect and out of range so the computer doesen't know what to do so it send more fuel to the injectors. It does not affect the engine but it will cost you more gaz.
I hope This help... and if I'm wrong, please correct me.

[kalooki]

Thanks everybody.

It appears to be a once off - it has not blinked since (just comes on at startup then eventually goes off).

So what sort of a job is replacing the coolant sensor? DIY or dealer?

[Smileybug]

Its a DIY no problem. You want to get a new o-ring when you get the sensor and a new clip, as the other has a chance of breaking when you take it out. But it all cost me $28 at the dealer, and I'm sure you could get it cheaper elsewhere. Takes no time at all. I'm pretty sure there is a thread or two around here that gives a good DIY on it.

Oh and when you get the sensor, make sure its green. Thats the revised one.

[JGC843]

Mine is doing this now. It started on a REALLY (95 F) hot day, and now every morning, or after the car has been sitting for awhile, it takes about 5 minutes for the light to go off. Mine is a 05' Vert, manual, 2.0, 46K miles, and it is still under dealer warranty.

If it just cuts off after 5 minutes, then maybe it's just a cold engine. It doesn't stay on long at all. If it begins to stay on longer, I'll take her into the dealer.

[05yellowbeetle]

5 minutes seems pretty long in 95*, mine is usually off in 1/2 mile or less (~2 minutes) at 85* or so. The only time it seems to stay on for a decent length of time is if the temperature is 60* or less. in NC when it is 20-30* it seems to take forever (10 minutes or more) to turn off.

[pinky]

the black sensors that you should replace with the green..

the dealer should replace them for free.. i think they just put out a recall. i was told by a friend at the dealership.

to the OP.. if the coolant level is low just add some distilled water. i think 50/50 coolant/water mix is standard, but the G12 (pink stuff) is good up to about 30/70 coolant/water

[HarlequinPixie]

booo... i just repased my coolant temp sensor and the little blue light still lites up randomly. (doesn't flash, just turns on and off for a minute or so.)

[mbetti]

I had all the same problems as described above. Replaced the temp sensor, new one is green old one is black. Hopefully the right one is the one tucked down in the black plastic pipe coming out of the end of the head near or under the air cleaner area. I noticed the blue warm up light goes out much quicker now. Test ran ok, but on my run to town the check engine light came on, not blinking, all the way to town and back. I made another look at my work and all looked fine, nothing loose. Test ran again and check light is out now. Not sure what it will do tomorrow. Is the computer having issues with the new sensor?

[petah]

Originally Posted by mbetti

I had all the same problems as described above. Replaced the temp sensor, new one is green old one is black. Hopefully the right one is the one tucked down in the black plastic pipe coming out of the end of the head near or under the air cleaner area. I noticed the blue warm up light goes out much quicker now. Test ran ok, but on my run to town the check engine light came on, not blinking, all the way to town and back. I made another look at my work and all looked fine, nothing loose. Test ran again and check light is out now. Not sure what it will do tomorrow. Is the computer having issues with the new sensor?

get a vag-com or obd2 scanner and check the CEL code.

[mbetti]

The light has not come back on. Blue light working perfectly. Is the diagnostic port simular to American cars. I have all kinds of heavy duty engine scanning equipment at work, maybe I should try.

[edgemaster191]

just be careful, mine did that when i test drove it lol

turned out to be the coolant sensor and the waterpump were both shot

mines a 2000 GLS 2.0 btw

[Chucktastic]

bringing up an old thread seemed like a good idea.

Pretty sure

red5

said was right its just the sensor that needs replacing.

For the past 2-3 months my BLUE temp light has stayed on the whole drive. Be it 10 mins to walmart and back or 2hrs at 80+ mph. Every now and than it will 'blink' for a little while then go back to solid blue. Never seen it turn RED (thank god).

But getting ready to take a 2500 mile round trip vacation, do you think I should change the sensor this week or think it will be ok without changing and just change it when either A) I get down to FL or B) when I get back to VA ?