Octavia RS 162 Coolant shut off Valve Wiring Loom

Hi Guys and Girls,

Hope you are all well.

Just wanted to reach out to the forum to see if anyone else has come across this and to make owners aware.

I own a 2016 Skoda Octavia RS 162 Wagon that has been meticulously looked after. 120,000KM with no oil leaks or water leaks. Waterpump and thermostat housing have been changed twice, once at 56k km under warranty and another at  (March 2024) 105,000km out of warranty.

Start of November 2024, My car suffered a complete engine power loss (Loss of Ignition power).

Taken to the dealer and it was determined that the DSG Coolant shut off valve (5Q0906457K) and Heater Coolant shut off valve (4H0121671D) have failed internally and began to leak coolant into the plug. This coolant migration has traveled along the engine wiring loom to the main connector causing the pins to corrode.

As a result, I am now up for a (worse case scenario) $17,200AUD repair bill or (Best case scenario) $7,500AUD. Depending on how bad the main connector plug has corroded into the Main body wiring harness and if the ECU is still ok.

This appears to be a well documented issue with VAG cars of that have the same part numbers, with Audi North America issuing a Technical Service Bulletin - https://static.nhtsa.gov/odi/tsbs/2015/SB-10058574-8951.pdf

And Ross Tech publishing a repair guide - http://wiki.ross-tech.com/wiki/index.php/P1888

Now mind you, no engine light has ever come up to warn me of any possible short or failure of the solenoids.

Here's a video of the diagnostic carried out by the Skoda Technician on my Car:

Other VAG owners on forums suffering from the same issue -
VWvortex: https://www.vwvortex.com/search/2816935/?q=Coolant+shut+off&o=relevance
Reddit: https://www.reddit.com/r/GolfGTI/comments/aitqg2/coolant_shutoff_valve_failure_p1889_n82_valve/
VWROC: https://www.google.com/search?q=VW+P1888+site.vwroc.com
BriSkoda: https://www.briskoda.net/forums/topic/517227-2017-skoda-kodiaq-coolant-leak-through-wiring-harness-to-ecu/
Audiworld - https://www.audiworld.com/forums/a6-c7-platform-discussion-194/coolant-mechatronic-tsc-connectors-2969953/
Audiworld - https://www.audiworld.com/forums/a8-s8-d4-platform-discussion-190/coolant-leak-through-wiring-harness-2862459/page5/

Hope this helps others out there.

Regards,

Kw0n3k