Help. 2 fans replaced with 1

GarrettB11 · Post by **GarrettB11** » 17 Sep 2022, 23:00

In my 2008 XC70, the original radiator fan set up had 2 fans. Evidently, Volvo now replaces these with a 1-fan system. I just installed the 1-fan system myself, and it is working, but I have an extra fan plug just dangling around not being used... I'm afraid the single fan isn't going to operate at all speeds or something.

There is NOTHING on the internet about going from 2 to 1 fans, only a mountain of information about going from 1 fan to 2 or more.

Does anyone have some experience, knowledge, or advice?

Thanks so much,
-gb

Post by **kallekula** » 18 Sep 2022, 05:49

Is there something wrong with the car? Have u taken it for a longer test drive?
You might be the pioneer on this one fan idea!

GarrettB11 · Post by **GarrettB11** » 18 Sep 2022, 16:51

kallekula wrote: ↑18 Sep 2022, 05:49 Is there something wrong with the car? Have u taken it for a longer test drive?
You might be the pioneer on this one fan idea!

The radiator fan wasn't working all the time, and the radiator had a leak in it. I replaced both those, and I read that it was a good idea to change the thermostat, so I did that too.

I ordered OEM parts from FCP Euro. They are the ones that told me the 1-fan system had superseded the old (original) 2-fan system.

So far I've let the car idle for 20 min, turned on the A/C for a good while, and taken it for a 20 mile test drive. All is well. No coolant warnings. Fan is running. A/C works. But again, I just don't know if the single fan has full capability.

Post by **kallekula** » 18 Sep 2022, 18:19

Try some gridlock traffic and see if it seems to hold up.
EDIT: attach some kind of test leads with a bulb to the fan. Pull leads into cockpit so you can see when/if fan starts. Could be wise to bring an obd reader too so you can measure temperatures.

Post by **pgill** » 19 Sep 2022, 09:23

My XC70 friend,

We are going to need more information.

I own two P3's and both are first cousins to your car

---2010 S80 3.2 Originally came with a dual fan and it was making noise so I replaced it with a Conti/VDO Dual Fan

---2008 LR2 3.2 (I know its a LAND ROVER) Originally it came with a single fan but I replaced it with a new VOLVO Dual Fan

The single Fan is bigger than the Large Fan in the dual Fan setup (but the Big + Small fan flow more air than the single fan)

The place that you will notice loss of FAN performance first is the AC at Idle on a hot day
(the AC won't work without air flow so either you need to drive or the fan needs to work)

Questions

1. Did you replace the FAN or the Controller for the FAN?

2. What part number did you buy?

Take care

Paul

GarrettB11 · Post by **GarrettB11** » 21 Sep 2022, 16:45

Hi pgill,
Thanks for some info.

I replaced the original dual fan, which had a controller for each fan, with a single fan that has a single controller.
The part number is: VOL-31686806
Part of my concern is that, the original dual fan had 2 plugs---once at each fan controller. Now, I just have a single-fan and am using the plug that had been going to the old large fan, and the other small plug is just sitting there not being used.

Post by **pgill** » 21 Sep 2022, 21:04

Garrett,

The Dual Fan for a 2010 S80 3.2 is 31686808 (this is exactly the fan that I installed in my LR2 it even came in a nice Volvo Box)

The single Fan is in fact 31686806 which is what you have

Both of these fans should have a single controller and a single connector with three conductors

B+ - Battery Plus

B- - Battery Minus

Control wire - a small wire that sends a PWM (Duty Cycle) to the controller.

I did a quick search and I found that Volvo has used a dual fan in a S60 that has two motor controllers and it is possible that someone modified you car's wiring harness to use the fan with dual controllers.

Take a careful look at the wiring to see if has been modified. If it has then they likely just spliced into the three conductors and if that is the case then the extra connection isn't much of a concern.

Post some pictures if you get a chance.

Take care

Paul

PS I did a little more research and here is what I found.

When you removed the Old fan you were suppose to disconnect the cars wiring harness from the Fan's wiring harness at the green arrow.

But instead you likely removed the connection at the red arrow and then you plugged into the new controller and now you have extra wiring.

Just remove the extra wiring and plug directly into the controller.

: Fan.jpg (102.19 KiB) Viewed 1123 times

Post by **pgill** » 03 Oct 2022, 10:08

Any update on the Fan?

Were you able to remove the extra wiring?

Thanks

Paul