Radiator Fan Won't Shut Off

[crazyvwvanman]

If your van came with factory A/C then the fan high speed relay is mounted separately to the body of the van above and to the left of the fuse/relay panel.
It is hard to see it.

Mark

[damagd]

Yeah, I think I found it. I can access it through the dash vent, but I have been pulling and wiggling it and can not get it to come out. I'll give it another try.

[crazyvwvanman]

You can borrow the "18 relay" from the main relay panel as a test replacement for that fan relay.


The power feed to that relay socket is live all the time, so careful!
Disconnect the battery ground cable when working in that area.

Mark

[damagd]

Well, I did get the fan to shut off by taking off the driver side headlight and unplugging the green tube thing back there, the name escapes me. The alternator problem is solved. When I looked at it I discovered a wire had broken. Reconnected that and it's charging fine now. Certainly I cannot use the 18 relay and drive with it in place of the fan relay, right? Even if I can get the fan relay off, which I am still struggling with. What about pulling the switch at the bottom of the radiator behind the lower grill and cleaning it? Someone suggested to me that it sounded like a stuck switch.

[damagd]

The resistor? I think that's what the green thing is called. Anyway I just plugged it back in and the fan is not running. But, once the fan kicks on again is it going to stay on again?

[crazyvwvanman]

You said that unplugging the temp switch low on the radiator didn't turn off the fan.
That means the temp switch isn't the problem.


Mark

[pdm777]

wild stab --- if the AC pressure is too high,
the fan will remain 'on' after shutdown. For very long time.
Trinary AC presure switch might be sending bad signal.
_________________
1990 Westy Full Camper

[pbooth59]

Hi all, new owner here. I'm having the same issue with the fan not turning off. Pulling the fan switch turns it off, as does pulling the #1 fuse. What does this mean? - Thanks!

[pdm777]

if your AC pressure is too high,
the fan will remain 'on' after shutdown.
For very long time.

Enough to kill your battery.
Put a set of AC gauges on it and see.

I recall unplugging the AC pressure switch
behind the rear cabinets would turn off the fan.

Lowering the AC pressure got it fixed,
On hot days, climbing hills, the high speed fan
should stay on for no more than 5 minutes after shut down.

Using a refrigerant like EnviroSafe (hydrocarbon AC alternative)
will lower pressures and cool much better than 134.
_________________
1990 Westy Full Camper

[fxr]

[pbooth59]

Awesome thanks, it does have factory A/C but I haven't used it yet and the problem wasn't there when I first bought the Van. I'll look into that fix and the switch and report back.

*Update* Got the new switch in, and it seems to be working! Thanks!

[chrowe]

My fan came on high and would not shut off unless I disconnect the battery.
Based on this thread I pulled out what I think is the high speed/3rd stage relay (see attached photos). Is there any way to test it to see if it has actually failed?

I have an 89 Syncro with no AC so I guess it is normal to have no relay in position 5. Is there a low speed/2nd sage relay somewhere else in my van?

It looks like those links to autohausaz no longer work. The current one is 70 Amps. I assume that is what is needed.

Maybe this one https://www.hansautoparts.com/357906381BRelay.aspx but it looks different.
or https://parts.vw.com/p/Volkswagen_1989_Vanagon/Relay/48302346/4H0951253A.html
or https://www.busdepot.com/8d0951253my (but it doesn't say the amps)
or https://www.busdepot.com/8d0951253 (but it has that extra metal tab)

[chrowe]

I tested the relay and it seems to make a connection when power is supplied to it. Does anyone know what activates the relays? It seem like in my case that might be the broken part?

[crazyvwvanman]

[chrowe]

Ya, I already tried that and it makes no difference.
I talked to a mechanic who thinks it is the resistor but I can't seem to find one online.

[crazyvwvanman]

The resistor can't really make the fan run all the time.
When the resistor fails it keeps the fan from running on the lower speed(s).

If the lower speed doesn't work that can make high speed run a lot so that is something that can result from a bad resistor.

Mark