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2007 VW Beetle convertible coolant (false) alarm

Hello! Thank you in advance to anyone who might have an idea of what the heck is going on with my Beetle.

This started a little over two years ago, right after I moved to California. My “check coolant” signal came on (red light with bell), so I pulled over, stopped my car, and let it rest for a few minutes. I assumed I needed to get it to a mechanic ASAP, but when I restarted my car, no warning light came on with it. Since I’d just driven cross-country and had my car tuned up beforehand, I thought it would be strange to have a low coolant level, and sure enough, it was fine. Since then, about a half dozen times a year, the same thing has happened. I just pull over and turn off the car, restart it, and it’s fine. It only happens in stop and go traffic–never on a highway.

On one occasion about a year ago, immediately after the light came on, I started to smell an overheated engine. By that time I had a neighborhood mechanic to have my car towed to, and he found a hose that had become loose, so he resealed it. For an unrelated reason, I’ve also had my car’s computer system reset twice, and before I went out of warranty last May I had a VW dealership carefully inspect my whole engine, and I was told there is absolutely nothing wrong with my car. And the alarm still comes on sometimes.

A little background info: I own my car, so there’s no hidden history. It has about 45,000 miles on it, and there was a year and a half before I moved to California that it was rarely driven (hence the low mileage for its age). I also live in Los Angeles, so it hits a ton of potholes (I currently need new shocks) and I rarely get to drive more than a quarter mile without having to brake for a light.

I’d love a diagnosis! Or at least reassurance that my current state of “not worrying” is okay for me and my silly car.

Are you checking the coolant in the radiator or in the overflow reservoir? The reason I ask is that my wife came home once with our 1993 Oldsmobile 88 and said that a warning light had just come on about a block from home. I checked and the low coolant light was on. The reservoir tank was almost overflowing. I let the car cool and removed the radiator cap. The coolant level was low. I added coolant, and wondered why the overflow tank was overfilled. The problem was that the hose from the overflow tank to the radiator was weak and would collapse when the radiator cooled down and the vacuum created was supposed to draw coolant back from the overflow reservoir. $2 worth of new hose cured the problem
My son had a similar problem with a 1995 Mustang after the radiator was replaced. He kept checking the coolant in the radiator and it was always full. The engine didn’t overheat, so he ignored the warning light. However, the Mustang did not have a warning chime thagt was activated.

I wouldn’t say this is something that would be wise to ignore. Overheating can cause problems that result in very expensive repair bills. Even a new engine. Find a shop straight away that specializes in VW’s. This should prove easy for an experienced mechanic to find the cause. It could be something as simple as a radiator cap that isn’t holding pressure.

Other likely possibilities are: the coolant leve (in the radiator) is low, the radiator fan isn’t working correctly, the radiator is plugged, the water pump is on its last legs, the thermostat is stuck, or there’s air in the cooling system that needs to be bled.

Does the “check coolant” light mean that the coolant level is low or does it mean that the car is overheating? If it means that the coolant level is low, but the coolant in the radiator is up to the top and there is coolant in the overflow register and the car is not overheating, there is probably something wrong with the warning system. On the other hand, if the “check coolant” light means that the car is overheating, then certainly have it checked out immediately.

Thanks so much, both of you! I’ll take this wisdom with me to my mechanic…

If you have mixed the new antifreeze that claims will mix with any coolent with the vw factory coolent you will get a froth that collects in the overflow tank and this froth wilkl set off a light. vw have a tsb on this topic.