Radiator fans is it on permanently ?

[Oldiebut goodie]

Just read that addition above - seems rather involved - you only need to put a switch that puts power to the relay that is already in place! (via the red/blue wire). That would give you the 2nd stage high speed. Why make it more difficult?

Are you getting the two speeds when you bridge the 2 different points at the connector?

[sternal]

Yes getting two different speeds when bridging IGNORE THIS


IGNORE THIS

[sternal]

If you had a ground on one wire at the connector something is wrong!...
Jumper from red/white to red/blue should give you high speed fan and jumper from red/white to black/red or red/black should give you low speed. Looks like that 20A fuse should be a 30A also.

I think you're right this sounds right and fuse changed to a 30a

I don't have a UK van its from Germany don't know if this would make a difference

Have now been out to the van to get these readings

NO IGNITION WITHOUT RELAY !

ONLY LIVE READING IS RED/WHITE

red/white to red/blue NOTHING
red/white to red/black FAN GOES
red/black to red/blue NOTHING

NO IGNITION WITH RELAY

ONLY LIVE IS RED/WHITE

red/white to red/blue NOTHING
red/white to red/black FAN GOES
red/black to red/blue NOTHING



ENGINE RUNNING WITH RELAY

red/white to red/black FAN GOES
red/white to red/blue NOTHING
red/black to red/blue NOTHING

Just to add this is a standard 30amp relay from local car spares so i dont even know if its right but according to guy should be fine
Will order the correct relay in the morning and retake readings once it arrives...but I expect they will be the same


Why are readings the same with or without the relay !!!!!

[Oldiebut goodie]

Ignition on shouldn't make any difference as if the radiator was very hot and you switched off you would want the fan to continue to run until the rad had cooled.

It seems to me that the relay is not switching now - either due to a dodgy earth or due to the power not being switched - possibly the red wire to the fan from the relay? Earlier you said that red/white to red/blue gave the fan but now it isn't - you must have changed something?
No point testing red/black to red/blue as they only carry the power from red/white.

[sternal]

Or I got it wrong the first time I wrote all my readings down this time so I know these to be correct.
I just went and checked all earths are connected.


You are correct it was doing this earlier but not now.

with either relay and no ignition on

red/black (middle) to red/white(left) fan on

&

red/white(left) to red blue(right) in other words two outer wires

I really feel like giving up and just fitting a switch...

oldiebut goodie what would you do ?

[Oldiebut goodie]

Have you messed with the wires to the relay on the rear of the relay/fuse board? One may be missing.
You could have burnt out the relay but that would be unlikely I would have thought, especially as you have a 20A fuse in there.
I would have left it alone to start with as the fan would only have come on when the radiator got hot enough which would be unlikely with around town use. It would only come on when the engine has pushed the temp up over the 3/4 mark.
You appear to be trying to fix something that wasn't broken to start with!

[sternal]

have changed the fuse to a 30amp

its very fair what you say...the earth terminals needed cleaning thats for sure but why was it missing the 40amp relay ? Is this not actually needed which is why it wasn't there ?



if didnt have a relay in the first place then wouldnt it have only had one speed setting on the fan ? YES NO ?

Will have a look at the wiring during the week and see if I knocked anything by accident...

As you say it doesn't get that hot and can always take heat off the engine having the hot air on ! ( Im good at hot air )

Is it worth ordering the correct relay from VW H ?

thanks once again...

[Oldiebut goodie]

Who knows why the relay was missing!
IF there was only a one speed fan the relay MIGHT not have been needed - the Vanagon doesn't seem to use a relay for the first stage. BUT you have the wiring for a 2 speed and did have 2 speeds. You say that the trigger wire for the relay is also present at the rear of the relay so it is pretty safe to assume that you have a 2 speed.
No point spending loads of money on a VW relay when it is just a standard 40A one.
You mustn't lose sight of the fact that the temp of the engine does not necessarily indicate the temp of the radiator. You need to ascertain the temp of the radiator at the switch area to judge whether the fan should be coming on or not. Due to the difficulty that people have with measuring this they swap out the temp switch whether it is working correctly or not. I should think that 99% of the time the switch is OK and the rad is just not reaching a high enough temp.
I checked all over my rad with an infra red thermometer and it was not getting anywhere near switching temps at any position.

[sternal]

You say that the trigger wire for the relay is also present at the rear of the relay so it is pretty safe to assume that you have a 2 speed.

but im still missing the 70amp relay above the earth crowns...so if im right from reading all MY hot air posts then its only ever going to work on single speed regardless of wether I can get it to work on both speeds when bridging...


would something like this be of help ?

http://www.ebay.co.uk/itm/Digital-Infra ... 3cd2f81505" onclick="window.open(this.href);return false;

Maybe its a trick VW played on the public !

[Oldiebut goodie]

I have the 70A relay most probably because I have a higher spec van and the rad fan is more powerful than yours. Not everyone seems to have the 70A separate relay. If you had one you would soon see the hefty great red wires for it - they are pretty unmissable.

[sternal]

I have the 70A relay most probably because I have a higher spec van and the rad fan is more powerful than yours. Not everyone seems to have the 70A separate relay. If you had one you would soon see the hefty great red wires for it - they are pretty unmissable.

could be as I have a 1.6 diesel non turbo and lets face it its never going to go fast enough to get hot...



think i'll buy that thermometer can use it on other things as well

[sternal]

I listed in the wrong section ! one forum member Oldiebut goodie has gone over and above giving some great advice

if you have a 1.6 diesel non turbo do you have No.5 relay ? does your radiator have a 2 stage fan ?

I dont have no.5 relay so wondering should it even be there !?! or was it taken out years ago...

take a look at thread

https://club8090.co.uk/forum/viewtopic.php?f=37&t=123809" onclick="window.open(this.href);return false;

many thanks in advance

(i know some of you think im bonkers or a joker on this site but I can assure im not ! )

[sternal]

Morning !

Took van to work so on way stopped off at mechanic explained all to him.

He had a look managed to get it to run on two speeds loose at back of fuse board...his honest opinion was by the time I've paid him to investigate as the wiring has clearly been played with bought new rad switch as this is prob o not working & relay etc and maybe still not solved it...was to wire the fan direct from the battery and have a switch inside ! He says he's done loads of these and as long as the temp gage is working then stop pancaking and go buy the stuff fit it myself as it easy and enjoy the van !


part of me wants to solve it though and the other part like he says don't start delving and throwing good money away to maybe not get the answer cos if someone has royally played with the wiring its how long is a piece of string !
His other thought was as its an ex post office van you never know that at some point it may have had other stuff done to it whilst it was a mail van...

Thoughts

[AdrianC]

So let's just go back a step here...

You have a terminal at the fan switch connector which has +12v all the time, yes?
Good.

Jump that to one connector, and the fan works, all the time, yes?
Good.

Jump that to the other connector, and the fan works, providing the engine's running, yes?
OK, I can live with that.

So the relay's preventing the high speed coming on when the engine's not running. That's probably a wise thing to do on a stop-start vehicle like a postie's van, to help prevent the battery being run flat enough to restart the van.

If that's really what you've got, but the fan isn't coming on when the engine gets hot, and the rad's equally hot all over, then just replace the fan switch.

[sternal]

You have a terminal at the fan switch connector which has +12v all the time, yes?
Good.

correct

Jump that to one connector, and the fan works, all the time, yes?
Good.

correct

Jump that to the other connector, and the fan works, providing the engine's running, yes?
OK, I can live with that.

No if I did that then nothing happens

if the two wires that are connected not the +12v feed are connected this will make the fan run on other speed...

all this without ignition on...

confusing isn't it !