Coolant Level Relay Toasted From Migrating Coolant

[Imatk]

So my coolant level warning light came on and I checked the plug on top of the reservoir and there was quite a bit of coolant in the plug itself and on the wires.

Well somehow, and I've never seen this before, the coolant actually migrated down the wire all the way inside the car to the relay switch where it fried the relay.

I have a relay on order, but my question is... do these wires need to be replaced or are they fine if I let them "dry out".

I don't want to put a relay in for it to just fry again from coolant.

I've taken off the relay pin housing from the fuse box and am in the process of cleaning and drying all of the coolant that is in the housing and on the other wires.

But thought maybe I was wasting my time if the coolant is somehow still present in the wire?

Also is there a way to future proof this so it doesn't happen again?

Thanks for any help

[ThomasD]

I have heard of this problem with Mk4 VWs, but not the older cars. You can find several threads on it for Mk4s. Here is one:

https://www.myturbodiesel.com/wiki/cool ... reservoir/

I doubt the wiring in your Scirocco needs to be replaced - just dry it out, check and clean the contacts, making sure there is no corrosion. But to stop this from happening again, you should replace the sensor in the overflow tank (assuming the tank itself is ok - no cracks or anything around the sensor). If the overflow tank is questionable, replace that as well.

[Imatk]

Yeah I have a new sensor and tank, probably going to replace the tank just in case. The only place that fluid was visible was actually inside the sensor clip so it must have come up through the prongs :/

Not sure what to do to make sure it doesn't happen again... very weird.

[Nate]

If it's made the copper inside the wires go black then it'll want replacing

[mark1gls]

Yes I've have read about this problem before on mk1 Golfs are you 100% sure it's coolant as common for water leaks from above the fuse box in the scuttle area.

[mr.brown]

Did you figure out how/why the leak happened? As above, water on the fusebox is usually an issue with the windscreen seal.

Also, what relay was it? (As there is no coolant level relay)

[mark1gls]

There is relay 42 or 43 which sits above the fuse box and that relay deals with the red warning light.

https://vwgolfmk1.org.uk/forum/index.ph ... t-flashing

[mr.brown]

There is relay 42 or 43 which sits above the fuse box and that relay deals with the red warning light.

https://vwgolfmk1.org.uk/forum/index.ph ... t-flashing

That explains it then - I don't have any of the upper relays

[mark1gls]

Not sure what year VW did this but it’s on my 88 car.

[Saboo78]

I have heard of this problem with Mk4 VWs, but not the older cars. You can find several threads on it for Mk4s. Here is one:

https://www.myturbodiesel.com/wiki/cool ... reservoir/
transfers paris airports
I doubt the wiring in your Scirocco needs to be replaced - just dry it out, check and clean the contacts, making sure there is no corrosion. But to stop this from happening again, you should replace the sensor in the overflow tank (assuming the tank itself is ok - no cracks or anything around the sensor). If the overflow tank is questionable, replace that as well.

Bon courage

[Imatk]

Yes I'm absolutely sure it was coolant. It smelled like coolant on the relay.

The sensor that I bought was aftermarket (couldn't find the OEM one) and it leaked through to the plug. So when I pulled the plug from the bottle it was pooled with coolant.

The relay was number 18 on my car '87

I've replaced it with a new sensor which, so far, hasn't leaked, but I'll be crafting a jump harness to prevent this from happening in the future.

[james butler]

you can strip some insulation off the wires and put candle wax onto the wire and then heat shrink over it.
this is what we do in robot washes to prevent the detergent and water working its way up the harnesses.
i can remember who it was but someone also had water make its way through the washer jet wiring harness down to the fuse box as they did a write up on here.