Yes it is a valuable feature in general. It has saved a lot of engines
including in a few of my own Vanagons over the years. It gives an
advance warning in many cooling system failures. My wife's BMW wagon has
it too and it gave us warning of a cracked plastic radiator pipe while
there was still plenty of coolant left circulating in the system.

The over temp function of the led is also great as an attention getting
device when the temp gauge reading is getting too high. I was climbing
an extreme grade in the sierras when the flashing light caught my eye.
Kaiser Pass is steep, narrow, and winding with only a single lane shared
by 2 way traffic so watching the road at all times is vital. Once I
spotting the blinking I pulled right over to hear boiling and see some
steam coming from the back. I soon figured out that the radiator fan
fuse had blown and the slow speeds combined with steep grades made the
fan essential to keeping the engine cool. I waited a while, added
coolant, replaced the fuse and went on my way. At 9000 ft in a remote
area with no cell coverage I felt pretty lucky.

Mark

Roy Nicholl wrote:
> They still share the function on new VWs.  The coolant light on my wife's 2006 TDi started blinking last November (temperature -10C) ... after we had the coolant flushed and replaced in August.  The mechanic had filled the system to barely reach the minimum level in the reservoir (in August).  Come winter, the level was not quite enough to satisfy the sensor on cold startup.   After the engine ran for a few minutes (no where near fully warmed up for a diesel), things had expanded enough to make the light go away.
>
> On 12-Dec-2014, at 16:54, mark drillock wrote:
>
>> The blinking temp gauge light is primarily for a HOT engine warning. The
>> coolant level warning is a secondary feature that was added later on
>> some VW models such as Vanagons. That is where they went wrong IMHO,
>> sharing the same flashing light between 2 warning functions.
>>
>>