Aircon And Cooling Fan/wiring

[cs.dobson]

I'm trying to fault find my aircon issue, here's the story so far;

I get an error code - P0691 Fan 1 Control Circuit Low

I can reset the fault which allows the A/C clutch to click in and run for about 5 seconds before cutting out, at that point the error code re-appears.

The engine fan never starts so the assumption is that either the fan is faulty or the control wire (lilac cable) is broken or there is a bad earth at the PCM unit.

The earth I'm no9t sure about as I would have though there would be other issues if that was at fault?

Either way I need to test the fan operation which I know can be forced into life by unplugging the ECT sensor lead but I can't find it. If it does come on then I know the fan is fine and the likely culprit is the cable or earth.

Problem 1; can some one help me find the ETC cable so I can test that?

Problem 2: If the fan is fine then does anybody have an idea of where the likely break point is in the cable or if the cable can simply be replaced by a new one to the PCM unit?

Cheers for any help

[jeebowhite]

to be honest, it sounds like the rad control unit has gone. Best thing to do, is to get the positive and negative and touch them straight to the battery and see if the fan spurs and stays. If it does, then your looking at wiring for sure, but I suspect once you do this, it will prove the control box is the fault.

[cs.dobson]

Hi, thanks for that, if I connect to the relay side I get nothing as I would expect as the relay hasn't activated but when connected directly to the fan the fan works. cabling to the relay from the PCM then?

[shaunytee1600]

Try checking to see if the system has enough aircon gas ?

Sent from my iPhone using Ford OC

[jeebowhite]

could well be the wiring,

You coudl try switching two relays to see if the problem stays or follows the relay.

[cs.dobson]

Aircon gas was the first step, sorry should have mentioned.

Which 2 relays? The relay that's the issue is the one attached to the fan housing, I am looking for a replacement but from what know it comes as a complete unit (no doubt so the stealers can make more money from us!). I am hoping to try to power the relay by wiring directly to the socket where the thin lilac cable connects but I'm not sure it's a 12v feed to that point as it comes from the PCM?

Cheers

[jeebowhite]

If its a standard 4 point relay then you can just grab one from the engine fusebox and swap it with the fan one, I dont recall what shape it is though.

[shaunytee1600]

you should have an ISO relay.

Sent from my iPhone using Ford OC

[stef123]

Are you getting power on the control side of the relay when the switch is activated? Have you got some scrap wire to remove/test the relay?

[cs.dobson]

The unit I'm referring to is more often called the cooling fan module, see link

http://www.ebay.com/itm/FORD-FUSION-COOLING-FAN-Motor-05-06-07-08-09-10-11-Module-BG13-8C609-AA-OEM-1-/121220026227?pt=Motors_Car_Truck_Parts_Accessories&hash=item1c3946cf73&vxp=mtr

If I connect 12 volts to the car side nothing but if connected to the fan side the fan works well.

[stef123]

The unit I'm referring to is more often called the cooling fan module, see link

http://www.ebay.com/itm/FORD-FUSION-COOLING-FAN-Motor-05-06-07-08-09-10-11-Module-BG13-8C609-AA-OEM-1-/121220026227?pt=Motors_Car_Truck_Parts_Accessories&hash=item1c3946cf73&vxp=mtr

If I connect 12 volts to the car side nothing but if connected to the fan side the fan works well.

Are you getting 12v at the control side of the relay though when the button is pressed? The coil could be be burnt out or the contacts could be stuck.

Sorry, just read your post again - your obviously not getting anything on the control side

[cs.dobson]

Yeh on the control side I have applied 12v and no fan operated but I now realise that I hadn't at that point turned on the aircon so it may well work but it's too dark to test tonight so I'll try that in the morning.

No wonder it wouldn't work from the control side!

If I turn the aircon on (I assume the engine will need to be on??) and then the 12v supply still wont turn the fan then I'm guessing it could still be the module or the cable linking to the PCM?

I don't have a spare module to test with but I could apply a test voltage to the link where the Lilac cable connects to but do you know if it's a 12 supply or not?

[mkaminski100]

I know that this thread is very old and the author didn't come back to state if he resolved it, so I hope the following will help others. 

Ford between 2006 and 2010 was using very cheap and thin wiring, so it's common to see corrosion on stress points. If you look at the fan control module, which is on the back of the fat (aluminium box with 2 plugs) there is one purple cable. This cable often corrodes or is damaged. It usually corrodes in the trunking running in the beam under the radiator, so it's a good idea to check resistance between the plug on the module and the ECU (for diesel models it requires drilling of the snap bolt to remove the security cover).

Here's the most common area where this cable fails:

https://mondeo-mk4.de/index.php/Thread/11612-Fehlermeldung-P0691-Kühlerlüftersteuerung-Kurzschluss-nach-Masse/

 

[Ru55a]

Hi

my son seems to have the same problem being reported here with his s max , we intend to check out the lilac wire issue first , but can anyone tell me if  adding new pice of wire what gauge should it be.?

cheers Russ