Ongoing change over valve issues on 991
#226
Instructor
Here are some links that i think will be of help to you.
http://plenums.blogspot.com/2016/10/...-overview.html
https://rennlist.com/forums/991/9128...ing-again.html
http://plenums.blogspot.com/2016/10/...-overview.html
https://rennlist.com/forums/991/9128...ing-again.html
#227
5th Gear
Join Date: Aug 2020
Location: Somewhere in Snohomish County
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Interesting discussion on the COVs. My 2015 C4S just now popped up the Cooling System Fault message as I was driving mysetlf to my office. I'm curious though for others with the same issue on the 991. The message was in grey on the MFD. Other's I've seen with the same fault were shown yellow. Does Porsche have a message color meaning for severity of the fault? I will need check with my obd2 scanner to find out more, especially to find out which one of the 8 COV's had triggered the warning. Any methods that you guys have? I will searching through this thread on ways to find out which ones had failed. Thanks all!
#229
I cannot remember if my message was in grey or yellow.
If your water temp was over 194F could be something other the COV. Just check.
If your coolant temp is normal very likely the COV. My reader does not test the COV so I used the diagram that 2-Rotor posted above to find it. I rigged a little test switch and wire and applied 12V to make sure I had the right one and it would not activate. Coupe of the others did.
I purchased the old style COV as I did not want to replace the COV harness as it is buried fairly deep in the engine compartment. You will need to remove the spoiler and when done clear the code with your reader. First time doing if took a couple of hours. Not hard but a little tight.
Good luck.
Drew
If your water temp was over 194F could be something other the COV. Just check.
If your coolant temp is normal very likely the COV. My reader does not test the COV so I used the diagram that 2-Rotor posted above to find it. I rigged a little test switch and wire and applied 12V to make sure I had the right one and it would not activate. Coupe of the others did.
I purchased the old style COV as I did not want to replace the COV harness as it is buried fairly deep in the engine compartment. You will need to remove the spoiler and when done clear the code with your reader. First time doing if took a couple of hours. Not hard but a little tight.
Good luck.
Drew
Last edited by DrewAltemara; 07-03-2023 at 10:43 AM.
#230
I have a friend in the HVAC business and he’s always told me that in the winter months you should turn on your AC on a few times for about 20 mins just to cycle it and keep it lubed. I used to work on aircraft (planes) and have probably mentioned here but I do believe our cars will do the same if not used somewhat regularly. Happy 4th all!!!
#231
Part numbers updated once again!
I recently lost heat on my 2014 911 C2 and I ordered the newest revision of the COV 7PP.906.283.P the part had a 2023 build date. Incidentally the old COV val e had a 2019 build date?
#232
Three Wheelin'
Ok, it appears the latest version of the COV is 7PP906283AA.
Having looked at this new version, it DOES NOT require a new wiring harness as it looks to be the same shape as the original COV Version .
So it went from original, to then B, then C, then went to F (new harness adapter necessary), then went to version P (new harness adapter necessary) and THEN went to version AA (harness adapter NO longer necessary)
Having looked at this new version, it DOES NOT require a new wiring harness as it looks to be the same shape as the original COV Version .
So it went from original, to then B, then C, then went to F (new harness adapter necessary), then went to version P (new harness adapter necessary) and THEN went to version AA (harness adapter NO longer necessary)
Last edited by roadsession; 09-25-2024 at 04:24 PM.