Cooling fan constantly running

Just had to get my V70 out of storage early due to a muppet failing my C70 on 'imaginary faults' (clearly totting for work and being reported to DOT!)

As usual the estates battery was as flat as a pancake but a quick boost start and drive charges it up again. However i have now got the cooling fan running in mode 2 (full speed) all the time so looks like the jump start has fried the relay? It never steps down to mode 1 ( air con setting).

Im worried this will burn the motor out fast not to mention its killing the battery every time I stop so i have to disconnect it every park up.

Is this likely to be the fault and is this the long rectanglular silver box attached to one of the fan supports or the relay under the bonnet lock plate please?

I've had this on my P2. Read and delete the codes using an OBD and it resets it back to normal. Hope that works for you.

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Originally Posted by uqj83l

I've had this on my P2. Read and delete the codes using an OBD and it resets it back to normal. Hope that works for you.

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Nice one cheers

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Originally Posted by uqj83l

I've had this on my P2. Read and delete the codes using an OBD and it resets it back to normal. Hope that works for you.

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Bill's correct!

Also, the fan is not controlled by a 2 stage relay. Your car has 2 PWM fans and they are controlled by a fan module via input from the ECM. If my memory serves me well, the fan's have infinate speed settings, but are princibly controlled by fixed percentage settings. ie, stage 1 = 12%, stage 2 = 21%, stage 3 = 39%, stage 4 = 57%......and so on so forth. The percentages are in VIDA, but don't ask me to find them as the percentages are not important. The speed of the fans is also dependent on whether the CCM/Aircon is switched on. ECM controls fan speed based on ECT readings.

On a side note....Is there anyway you can leave your car battery on charge using a smart battery maintainer? Getting constant flat batteries is not good for the battery and cause it to sulphate very quickly. Maybe even two Solar chargers plugged in...one in the cigarette lighter socket in the boot and one connected to the battery. This will give you 0.4amp trickle charge, which is enough to maintain a 'charged' battery but will not charge a flat battery.

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Originally Posted by LeeT5

Bill's correct!

Also, the fan is not controlled by a 2 stage relay. Your car has 2 PWM fans and they are controlled by a fan module via input from the ECM. If my memory serves me well, the fan's have infinate speed settings, but are princibly controlled by fixed percentage settings. ie, stage 1 = 12%, stage 2 = 21%, stage 3 = 39%, stage 4 = 57%......and so on so forth. The percentages are in VIDA, but don't ask me to find them as the percentages are not important. The speed of the fans is also dependent on whether the CCM/Aircon is switched on. ECM controls fan speed based on ECT readings.

On a side note....Is there anyway you can leave your car battery on charge using a smart battery maintainer? Getting constant flat batteries is not good for the battery and cause it to sulphate very quickly. Maybe even two Solar chargers plugged in...one in the cigarette lighter socket in the boot and one connected to the battery. This will give you 0.4amp trickle charge, which is enough to maintain a 'charged' battery but will not charge a flat battery.

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As the cigarette lighters only work with the key in position 1 or 2 will they actually take a charge if the ignition is in position 0?

Quote:

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Originally Posted by LeeT5

Bill's correct!

Also, the fan is not controlled by a 2 stage relay. Your car has 2 PWM fans and they are controlled by a fan module via input from the ECM. If my memory serves me well, the fan's have infinate speed settings, but are princibly controlled by fixed percentage settings. ie, stage 1 = 12%, stage 2 = 21%, stage 3 = 39%, stage 4 = 57%......and so on so forth. The percentages are in VIDA, but don't ask me to find them as the percentages are not important. The speed of the fans is also dependent on whether the CCM/Aircon is switched on. ECM controls fan speed based on ECT readings.

On a side note....Is there anyway you can leave your car battery on charge using a smart battery maintainer? Getting constant flat batteries is not good for the battery and cause it to sulphate very quickly. Maybe even two Solar chargers plugged in...one in the cigarette lighter socket in the boot and one connected to the battery. This will give you 0.4amp trickle charge, which is enough to maintain a 'charged' battery but will not charge a flat battery.

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Cheers Lee but same question as Steve will a solar panel work via a 'dead' fag lighter as in with ign off? My storage yard sadly miles from anywhere and no power there so solar only option. The car is due a new battery as ive put a new one on the C70.

Wanted to ask, whats the most reliable web site for OBD codes please?

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Originally Posted by stribo

As the cigarette lighters only work with the key in position 1 or 2 will they actually take a charge if the ignition is in position 0?

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Interesting point!

I have 3 fag sockets in my car, center front dash, rear seat back of center console and in the boot right side of panel.
The two at the front go dead when ignition off but I'm sure the rear boot one stays live!
I'll check it later...

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Originally Posted by uqj83l

I've had this on my P2. Read and delete the codes using an OBD and it resets it back to normal. Hope that works for you.

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Hi
tried the OBD reader this morning NO CODES so its not that causing the fan problem :( So could it be the thermostatic module or relay?

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Originally Posted by Tee5alive

Hi
tried the OBD reader this morning NO CODES so its not that causing the fan problem :( So could it be the thermostatic module or relay?

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If it's a TRUE OBD code reader you won't get any codes out of it unless they are "Emissions" related. Which this isn't.
Chances are there are faults stored, but it just won't read them.
And as Lee has said you need to check other modules like CEM & CCM as there could be potential clues within them.

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Originally Posted by Tee5alive

Hi
tried the OBD reader this morning NO CODES so its not that causing the fan problem :( So could it be the thermostatic module or relay?

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Cheap code readers don't always read ALL the fault codes, especially in other modules unrelated to the ECM.

Late Peugeot/Citroen models also have similar fail safe's built in. When battery voltage falls below a particular level, the cooling fans actually come on at 100% and stay on until you supply the battery with charging voltage from either a donor car or by boosting the vehicles battery. There will always be multiple 'low voltage' CAN fault codes stored across most modules, especially the ECM, TCM, ABS, CEM, REM.

Most cheap hand held code readers are only able to communicate with the ECM, therefore, low voltage fault codes will remain in all the other modules and the fans will persist.

If the A/C charge is too high the fan will run continuous also some models it can mean a MAF problem!

Hi,as 960kg suggested...check your maf..faulty maf can throw the fan on and will not always give a fault code

There was a thread on here once about a fan running constantly and the problem was that the fan wiring runs under the subframe near the front and is prone to chafing through .
Probbly not , but worth checking out.

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Originally Posted by Tee5alive

Cheers Lee but same question as Steve will a solar panel work via a 'dead' fag lighter as in with ign off? My storage yard sadly miles from anywhere and no power there so solar only option. The car is due a new battery as ive put a new one on the C70.

Wanted to ask, whats the most reliable web site for OBD codes please?

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I checked the rear cigarette lighter 12v socket and it is permenantly live! So you could plug a solar panel into that socket and it would maintain a charged battery. :wink:

The other two 12v sockets work off the ignition (Front center console and rear seat passenger console).

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Originally Posted by LeeT5

I checked the rear cigarette lighter 12v socket and it is permenantly live! So you could plug a solar panel into that socket and it would maintain a charged battery. :wink:

The other two 12v sockets work off the ignition (Front center console and rear seat passenger console).

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Checked the xc90 at the weekend, and the boot one is permanently live, and brings up a message on your dash, to let you know when it's in use.

Hi

I have had this on my S60T5 P2. It sounded if the fan was going full blast all the time and the car was ready for lift off - if airport runway found.

There are two sensors that affect the fan. One is in the engine coolant side, the other is in the Air Con. side. If either packs up then the fan goes ballistic. Mine was the Air Con. sensor.

Best of luck

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Originally Posted by Peter68

Hi

I have had this on my S60T5 P2. It sounded if the fan was going full blast all the time and the car was ready for lift off - if airport runway found.

There are two sensors that affect the fan. One is in the engine coolant side, the other is in the Air Con. side. If either packs up then the fan goes ballistic. Mine was the Air Con. sensor.

Best of luck

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Hi All,

I have this issue for the 3rd time now on my R! First time the ac juice was found to be low (probably not topped up years pre me buying - bought a whole thermostat housing but never fitted when regas sorted it), that fixed it then, then about 8 months later the same but this time AC people traced to two duff O rings, these we replaced and all fine for another 6 months or so. Now just started doing it again (fan starts 3 second after engine fired up and runs constantly). Took to AC place expecting leak fro somewhere, but they said AC side is all spot on, no leaks, working perfectly and to left should be at.

Hmmm!!!

So Peter68 is saying it it is the water coolant sensor or the an AC sensor. I took the new sensor out of the brand new thermostat housing I remembered I had and swapped that over (5 min job), no difference. Fluid up to the mark on the coolant expansion tank.

So am I looking at the AC sensor and what sensor(?), did I see someone say a pressure sensor on AC system?

Not plugged VIDA in yet as it normally take me 20 goes to ever get the thing to talk to the car.

Quote:

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Originally Posted by stribo

Checked the xc90 at the weekend, and the boot one is permanently live, and brings up a message on your dash, to let you know when it's in use.

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Yep, V70R does that too.

Quote:

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Originally Posted by jellison

Hi All,

I have this issue for the 3rd time now on my R! First time the ac juice was found to be low (probably not topped up years pre me buying - bought a whole thermostat housing but never fitted when regas sorted it), that fixed it then, then about 8 months later the same but this time AC people traced to two duff O rings, these we replaced and all fine for another 6 months or so. Now just started doing it again (fan starts 3 second after engine fired up and runs constantly). Took to AC place expecting leak fro somewhere, but they said AC side is all spot on, no leaks, working perfectly and to left should be at.

Hmmm!!!

So Peter68 is saying it it is the water coolant sensor or the an AC sensor. I took the new sensor out of the brand new thermostat housing I remembered I had and swapped that over (5 min job), no difference. Fluid up to the mark on the coolant expansion tank.

So am I looking at the AC sensor and what sensor(?), did I see someone say a pressure sensor on AC system?

Not plugged VIDA in yet as it normally take me 20 goes to ever get the thing to talk to the car.

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You need to check the fault codes in the ECM.
Fan speed is ECU controlled, governed by information from certain sensors, ie, Coolant, A/C switch.
You need to see what the ECM is seeing in live readings, in order to determine the fault.

Could also be a faulty relay.

Quote:

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Originally Posted by LeeT5

You need to check the fault codes in the ECM.
Fan speed is ECU controlled, governed by information from certain sensors, ie, Coolant, A/C switch.
You need to see what the ECM is seeing in live readings, in order to determine the fault.

Could also be a faulty relay.

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OK Lee will try to get to it over next day or so (scan with Vida).

Didn't someone on here say the relay for this was no longer there for our cars.

Been behaving itself fairly ok last 6 months, replaced tow bar with old one off T5 with removable hitch and fix reverse sensor going out (alot in one of these bumpers vs a base p2!) and front bumper off to replace both horn (one of them has never worked), alot of time on hands at present!!

Will try to post up codes if I can get my old pc with vida to work and remember how to scan, and will post code/s.

Cheers
Jon