new to me 2000 GTS overheating within minutes.

JDMB20TDA

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I picked up a 2000 GTS about a month ago and haven't had nice enough weather to actually drive it. Now that we've had some nicer days (& roads clean from road salt.) here and there I've finally been able to take it out... and the vehicle is overheating.
After a short time diagnosing the issue I was led to the seemingly common fan relay circuit failure.
dummy light/coolant temp gauge pegged.
cooling system trouble codes, coolants full and pressurized.


EDIT; looks like its not just a fan/ relay issue after all. with highspeed fan kicking it is still overheating in minutes.


I've scoured the boards with the help of some other owners and most of the old resources are outdated and no longer have working pictures or updates on the the solution.
the vehicle has 46XXX miles.
@ 41k 2013 thermostat & flush
@ 42k 2015 thermostat, flush, water pump & nearly every cooling system gasket.
so there's a history of this vehicle overheating but, seems like the mechanical/heat exchange portion of the system has been ruled out for the most part.
originally it seemed like rewiring the PDC with beefier gauge wires or even piggy backing the existing wires as a redundancy was a proposed solution. there was never any follow up to whether or not this was the cause. but likely just a bad design all around.
another proposed solution was dated and/or overheating relays, this could be the case with my situation as they seem to be the factory siemens VF4-15F21-Z05. Finding these that aren't used or "a comparable product" seems like commonplace.
finally it seemed like a lot of people were blaming the actual relay socket for the cause of the overheating, corrosion or poor worn contact between the connector and the relays themselves.
so far I picked up a local universal 40a 5 pin relay. its a copper brass contact unit so better than some of the others (aluminum contacts/lower heat ratings) available at other local auto parts stores.
I plan to run this for the time being,
https://shop.advanceautoparts.com/.../carquest.../12458954-P
I did order some 50a 5 pin silver alloy contact rated to 125c as a more permanent option going forward.
https://www.amazon.com/dp/B013EO7SDK...
my plan is to first contact clean the sockets and make sure none are pushed in from overheating their plastic housing.
then reinstall the new known good relay and fire it up make sure the high speed fans come on and the system runs as it should.
would you recommend any type of dielectric grease on the relay pins?
If anyone has a definitive solution on what the cause of these failures are or links to a working write up id be very appreciative.

got the new cheap local part shop relay installed and the high speed fans kicking in, still over heats within 4 minutes of running.
being the thermostat was replaced twice and the water pump as well in 2015 id assume its the updated design (non plastic failure unit.)
what is the suggested next course of figuring this issue out?

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JDMB20TDA

JDMB20TDA

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Full heat,
highspeed fans kicking on @ 216/217f blowing cold. over heating in minutes.
 

daveg

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Does it overheat with the Fan running?
Feal the upper and lower radiator hose, are they both hot when overheating?
 
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