Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Reply
 
LinkBack Thread Tools Display Modes
Old 08-19-2014, 08:06 AM   #1
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Flashing Temp Light

On my drive to work, the temp light began slowly flashing.

New tank, new cap, temp normal, coolant tank half full......

Any ideas?
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 08-19-2014, 08:18 AM   #2
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 726
From a Search for the explanation....

From Loren@ rennlist -- 12 years ago!

Here is the long explaination 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."


If you have replaced things -- I would check that the sensor connection is secure, or maybe replace the sensor.

Mike
__________________
Drivers: '08 Cayenne Turbo, 96 993 Çab/Tip (wife's) & '92 964 Cab
Race Cars: '75 911 RSR Clone & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 08-19-2014, 08:29 AM   #3
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Does it dead cold ....
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 08-19-2014, 08:33 AM   #4
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 726
Quote:
Originally Posted by peterbrown77 View Post
Does it dead cold ....
Than it has to be something related to the coolant level sensor.

It's either bad or poorly connected.

Mike
__________________
Drivers: '08 Cayenne Turbo, 96 993 Çab/Tip (wife's) & '92 964 Cab
Race Cars: '75 911 RSR Clone & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 08-19-2014, 11:04 AM   #5
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
A half filled coolant tank might be too low. There are indicators on the level sight and depending on what you consider half full might be just low enough to consider 'low'
epapp is offline   Reply With Quote
Old 08-19-2014, 12:35 PM   #6
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
I filled to coolant tank almost to the top at lunch today. Started the car from cold, light still blinking.

Left work at the end of the day, checked the level (still full), light still blinking.

At the same point on the highway where it started blinking this morning, but going in the opposite direction, it stopped blinking.

So I'm figuring some kind of coolant-level-sensor-underground-doggie-fence in the vicinity of Haddam CT as the likely culprit. Who's with me?
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed

Last edited by peterbrown77; 08-19-2014 at 12:39 PM.
peterbrown77 is offline   Reply With Quote
Old 08-19-2014, 12:55 PM   #7
Engine Surgeon
 
Join Date: Aug 2008
Location: Cleveland GA USA
Posts: 2,424
Quote:
Originally Posted by peterbrown77 View Post
I filled to coolant tank almost to the top at lunch today. Started the car from cold, light still blinking.

Left work at the end of the day, checked the level (still full), light still blinking.

At the same point on the highway where it started blinking this morning, but going in the opposite direction, it stopped blinking.

So I'm figuring some kind of coolant-level-sensor-underground-doggie-fence in the vicinity of Haddam CT as the likely culprit. Who's with me?
Watch closely in the coming days to ensure that you don't encounter intermix in the oil or coolant. This is a classic scenario that could be a precursor to something that you can catch early on.
__________________
Jake Raby/www.flat6innovations.com
IMS Solution/ Faultless Tool Inventor
US Patent 8,992,089 &
US Patent 9,416,697
Developer of The IMS Retrofit Procedure- M96/ M97 Specialist
Jake Raby is offline   Reply With Quote
Old 08-19-2014, 02:46 PM   #8
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
I will.

At first I discounted it because I was having a heck of a time with my new coolant tank's bleeder valve AND the cap. I had condensation about the reservoir and it was a combination of a bad o-ring and the cap. It's been dry the past week but I thought perhaps through all the fiddling enough had evaporated to make the level borderline. Kind of surprised that topping it off didn't eliminate the light.
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 08-20-2014, 03:41 AM   #9
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Quote:
Originally Posted by Jake Raby View Post
Watch closely in the coming days to ensure that you don't encounter intermix in the oil or coolant. This is a classic scenario that could be a precursor to something that you can catch early on.
Jake -

I've been pondering this.

With a cold engine, I filled the coolant tank to the filler neck and started the engine. The light slowly blinked immediately, indicating low coolant which was clearly not the case.

Do you agree that it must be the sensor?

TIA
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed

Last edited by peterbrown77; 08-20-2014 at 08:18 AM.
peterbrown77 is offline   Reply With Quote
Old 08-20-2014, 07:52 AM   #10
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
It would either be the coolant level sensor gone bad, or the engine compartment sensor gone bad, since either can trigger the slow blinking coolant light.
epapp is offline   Reply With Quote
Old 08-25-2014, 03:28 PM   #11
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
And a week later, it started flashing again. Coolant tank is full, and even does it from dead cold so the overheated engine compartment doesn't make sense.

Unplugged the coolant level sensor and tried (as best I could in the dark) jumping the connector with a paper clip. Didn't help.

Any thoughts?

And: Where is the engine compartment temp sensor?
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed

Last edited by peterbrown77; 08-26-2014 at 03:55 AM.
peterbrown77 is offline   Reply With Quote
Old 08-26-2014, 03:49 PM   #12
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Beuhler? Beuhler?

Hahah.
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 08-27-2014, 07:55 AM   #13
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
Well the problem is one of two dead sensors then (or both). I'm not sure what a good 'full' reading looks like to the ecu from the coolant level sensor, so shorting the two wires might still mean 'coolant level low' to the computer.

Since it probably DOES work like you thought (two wires shorted when coolant level is good), check the engine temp sensor. Its on the passenger side intake manifold between the throttle body and the plenums that attach to the head, you cant miss it, its the only sensor with wires coming out of it atop the passenger intake. Maybe there are some docs online that explain how each sensor works so you can test them (I dont have the bentley book with me all summer)
epapp is offline   Reply With Quote
Old 08-27-2014, 09:33 AM   #14
Registered User
 
Join Date: Jan 2013
Location: Phoenix, AZ
Posts: 231
If you had a durametric you could take a look at the engine compartment temperature. That would show that value that the engine compartment sensor is sending. When I had that issue, it was the engine compartment sensor fell out of it's grommet and was laying on the manifold. That would not explain a blinking light when the engine it cold but a durametric will show the value it is sending (e.g. is that sensor bad. I also wonder if the engine compartment sensor was bad if the engine compartment fan would be running????
runjmc2 is offline   Reply With Quote
Old 08-28-2014, 10:52 AM   #15
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
You would think that if it thought the compartment was overheated, the fans would be going full bore.
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 08-30-2014, 07:12 AM   #16
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
In Porsche fashion, they decided to go the other way - the coolant level sensor is a normally open circuit. Unplugging the connector made the light stop flashing. Who da thunk it?
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed

Last edited by peterbrown77; 09-02-2014 at 08:26 AM.
peterbrown77 is offline   Reply With Quote
Old 09-01-2014, 02:30 AM   #17
Registered User
 
Join Date: Aug 2014
Location: California
Posts: 37
Did u check the coolant temp reservoir?
guesswecan777 is offline   Reply With Quote
Old 09-02-2014, 08:26 AM   #18
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Quote:
Originally Posted by guesswecan777 View Post
Did u check the coolant temp reservoir?
I think I know what you mean, and - yes - the level has been fine all along.
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 09-07-2014, 10:51 AM   #19
Registered User
 
Join Date: May 2011
Location: Essex, CT United States
Posts: 299
Another pleasant hour of my Sunday dealing with Porsche "engineering" (if it can be called that).

Replaced the coolant level sensor with new, plugged it in, and drumroll ----- the light still flashes. So, if it's unplugged it doesn't flash. Which it currently is. I'm not going to get into the rank stupidity that has me remove 2 pieces of carpet and then loosen the entire tank to get the sensor out because they thought it would be a grand idea to position the sensor directly above one of the body seams so you can't drop it out without a written consent decree.

I guess it has to be the float? I can see that it is at the top of it's travel when it reaches a push-on retaining clip. Maybe I should somehow push the clip farther down the float's spindle?
__________________
2002 Boxster S, Arctic Silver, 18" Turbo Wheels, 6-speed
peterbrown77 is offline   Reply With Quote
Old 09-08-2014, 01:08 AM   #20
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
Did you check the engine compartment temp sensor for proper functionality?
epapp is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 04:51 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page