Coolant temperature warning light flashing, temperature pegged on low end of scale

[themetalmen]

I have a 2003 base model Boxster with the 2.7L engine.  My coolant temperature warning light is flashing slow.  The temperature needle never moves.  It stays pegged on the low end of the temp scale.  My coolant level is good.  I have replaced the temperature sensor with no change.  Anybody have any suggestions what it could be?  One of the cooling fans used to always whine for 20-30 seconds on start up and then go away.  I have noticed the last few times I started it the whine is not present.  Could that have anything to do with it - one of the fans?  My first thought is no - if a fan failed, the temp would rise.  Any help woudl be aprpeciated.

[Loren]

 

Covers all Carrera (996), GT3, TT / GT2 and Boxster (986) cars

Here is the long explanation from the service manual on the flashing coolant light.

"Four functions of the coolant warning light:

1. Engine coolant level too low -- light flashes slowly (0.5 Hz)

2. Engine compartment temperature too high -- light flashes slowly (0.5 Hz) (engine compartment blower might be faulty)

3. Engine coolant temperature too high -- light is lit; pointer on the right

4. Temperature sensor at water outlet faulty -- light flashes rapidly (1 Hz) ; pointer on the right

Note: The temperature warning in point three is indicated if the conditions "engine coolant temperature too high" and "engine coolant level too low" are present simultaneously."

[themetalmen]

Loren,

 

Thanks for responding.  The functional description you have provided is helpful.  Unfortunately for me, my issue doesn't seem to fall neatly into one of those categories.  My coolant level is good and I have found no evidence of leaks.  It can't be engine compartment temp too high, because the light blinks right from ignition on.  The temp needle pegged to the low end is not mentioned above either.  I have changed the coolant temp sensor.  That seemed to be the root cause of the few similar thread I have found so far in the forum.  I am hoping to find others that had to result to different means to resolving this issue.  As before, all advice is welcome.

 

[themetalmen]

Loren,

 

It appears I spoke too soon.  Apparently it takes a few minutes for the car to acknowledge the new sensor.  I watched the video linked below.  The author gives some information that is good and some that is not.  One thing he mentioned is that after connecting the new sensor, the problem was still present.  He took his car on a test run and after a few minutes, things started working correctly.   I tried the same thing.  Took the car for a 30 minute test run.  About halfway in, teh temp needle finally started moving and the light went out.  Temperature was in the 180-185 range the rest of the trip.  Looks like problem solved.

 

[Loren]