Berlingo fan stays on

[evanmjones]

Hi,

I have a 2001 Berlingo Electrique. While I was away last week and the van parked up in the drive the radiator cooling fan came on for no discernable reason. It kept on going for a few days until the batteries, 12v and main, were exhausted.

When I got back I heard about this and also found out it wouldn't charge. The 12v battery was very flat so I recharged and reconnected it. The fan did not start. I connected up the van to recharge it, the fan started as the charging started and now, once again, will not turn off.

If I disconnect the 12v battery the fan stops. It comes back on when I reconnect it.

The van drives fine. Seems to have no other problems apart from the fan stuck on.

I don't have a manual or wiring diagram and as far as I can work out the nearest garage that can work on an Electrique is a couple of hundred miles away.

Is there anyone out there that's experienced this problem, can offer any advice, or has any information, whole or part, that may help resolve the issue? Any advice much appreciated.

Thanks!

Evan

[Grumpy-b]

Have a look at this I think you have a similar problem. A potentially duff temp sensor.
http://www.batteryvehiclesociety.org.uk ... php?t=1704

[timpootle]

Hello Evan! You found us, then. Hope GrumpyB's link will help fix your problem.

[ChrisB]

Sounds like the standard dead 12v Aux battery fault causing the DC/DC to run all the time

I'd go with changing (not charging) the 12v for a new one first, unless you carry out a propper load test on a fully charged 12v and its deemed OK.

One thing though, its REALLY not good to disconnect the 12v battery with the main traction pack battery still connected as it can damage the DC/DC converter.

The sequence to try and ALWAYS follow is :-

1) Remove a traction pack fuse (easy one is just behind the 12v battery)

2) Disconnect the 12v battery

Reconnection is the reverse i.e 12volt first THEN replace the main traction fuse.

ChrisB

[evanmjones]

Hi All,

Many thanks for the advice, it's really appreciated.

FTR, for completeness of the post, I had a note from Evan Taur suggesting resetting the controller by removing a traction fuse as one option to try. I took the advice, removed the two main fuses (fan stayed on); waited a couple of minutes, then re-connected. Fan still on. Removed fuses again, disconnected battery, fan went off. Re-connected battery, fan came back on. Re-connected the main fuses, fan stayed on. Waited a few more minutes. Fan still on.

Disconnected the main fuses and thought I'd wait 5 minutes. Got absorbed in some work and forgot! A couple of hours later - great! The fan's stopped. Replaced main fuses, still no fan start! Turn key and.... everything else has stopped too. Swear a bit. Sure enough, 12v battery run flat by running the fan again. Recharged it, replaced it, fan comes on again. Replace main fuses, fan stays on. Leave it for a bit, fan still on. Remove main fuses, disconnect 12v battery, fan stops.

Thinking out loud:
* Wondering if the 12v should be running down that quickly with just the fan connected. After charging it showed 13.6v across the terminals, didn't leave it and check again later though.
* When the traction batteries were very flat but the 12v was charged the fan didn't run. Thanks to Evan Tauer I now know that this is because the controller would have been locked out because of the flat traction batteries. So I guess it follows that the relay can't be stuck on or re-connecting the 12v would have re-started the fan even thought the controller was locked out.

Which leaves me I guess with a dodgy 12v battery, or a duff temperature sensor. In the happy teenage days of dismatling my Vauxhall Viva batteries wither worked or didn't so 'testing' was 'does it turn the engine over after it's been on charge for a day.'. How /should/ one assess a battery?

I'm assuming the temperature sensor for fan initiation is on the coolant circuit somewhere?

Once again, many thanks for the responses.

Evan

[gwing]

Hi Evan,

If looking for a simple test I would first swap the battery for a good one (if I had a spare) and see if it fixes the problem. If it does I think you then know enough about how 'fit for purpose' the existing battery is

Failing that you can charge the battery and then discharge through a known load (such as a headlight) which will give you an idea of how well the battery performs compared to its nominal capacity. There are I'm sure more scientific methods such as applying a high load and measuring voltage drop which could be compared to that of a good condition battery or the manufacturers specification.

To my mind though both those methods suffer from the problem that although you may get numbers you don't actually know how bad a non good battery has to be in order not to function effectively in a given application. So you may in my book just as well charge it up, give it some TLC in terms of water top up and plate desuplhating, and then see if it works OK - if its still giving trouble its new battery time.

That said I would have thought it likely that if the battery is starting to fail the problem would be (at least temporarily) fixed by you recharging it. As that didn't fix it my money would be on the previously suggested idea of the temperature sender being faulty/loose etc.

Listen to the folks here that know what they are talking about & have had Blingo's for a lot longer than me though

[ChrisB]

Really does sound like a dodgy 12v to me (could be wrong though)

Easy way to check it is pull a traction fuse out and thus disabling the dc/dc convertor, then turn on the ignition and then the headlights.

The 12v "should" be able to maintain the headlights on full beam for a good 15-20mins plus and still be above 12v or a shade below, but I'd like to think on a good battery it should be able to stand a 12-15amp load for that time pretty easily.

I suspect when you do this you'll find it will fall away pretty quickly to 10v or less i.e one cell has died, if thats the case its new 12v battery time, and I wouldnt recomend running her until you change it as it will be causing the dc/dc convertor quite a bit of grief.

Load test the 12v first, charging it only without carrying out a load test wont show the fault up.

Of course if the 12v isnt the problem and is quite happy being loaded up then it could be the sensor at the front throwing a wobbly.

ChrisB

[evanmjones]

Thanks all - very grateful for the ideas.

OK - battery test. Disconnect the traction fuse to stop it recharging the 12v; check the voltage; see how long it takes to drop to 10v. Fair enough. I can do that.

"could be the sensor at the front throwing a wobbly". Like the sound of that also. Specifically the word "front" which implies rather easier to access than most things Citroen do (ex 2CV owner). Is that the temperature sensor?

Cheers,

Evan

[ChrisB]

Ah hang on I'm getting me knickers in a twist again

Right if memory serves me correct the only two sensors that bring on the Rad fan are the one in the top front battery pack and one in the controller itself.

Have no idea about the one in the controller but the one in the top front battery pack requires the controller, 12v battery and generally the petrol heater to be removed so you can then pull the pack forward and out so you can remove the top to get to it.

You can see the two thin wires going to that battery pack and onto a connector on the right hand side I think.

I'm hoping that you'll find its just a tired 12v battery

ChrisB

[Grumpy-b]

You can test to see if it is the battery pack sensor. This is the main one that fails and brings on the fans, pumps etc.
Gat a 3k resistor (or near value)
I assume all power is disconnected, and that the 12v battery is fully charged and in good condition. ie holding a voltage well above 12v probably nearer 13.5V
On the Nearside front of the top battery pack at the join between the two halves of the case, is an electrical connetor. Like all the others push in the wire clip which releases the catch. Pull down at the sam etime. It will be stiff. Insert the wire ends of the resistor in the connetor. Insulate this with some tape to hold the leads apart and hold it into the socket. Take the socket to the battery case or the nearby cables.
This will now make the controller think you have a temp of about 20 to 25 degrees C. Fans should not run .
So now when you turn on the power, 12 v first, then insert the traction fuses, nothing out of the ordinary should occur.
If the fan still run, then you have a more complex failure, if they dont run, then the problem is the temp sender. I have previously done a piece on how to replace this, and I can help with an exchange sensor, unfortunately my spare hasnt been returned from another person with the same problem, so I can only re-furbish your own. Send me a PM if you need such help.

Grumpy-b