Berlingo dw8 cooling fan not working

[mighty]

I have a 2005 berlingo 1.9D where the cooling fan has stopped working. I have seen the temperature go up to 110 degrees without the fan coming on. When testing with lexia I can hear a relay working but nothing else happening. When I connect 12v directly to the fan, it works.

Lexia gave me code P1519 "Intermittent fault, cooling function inside ecu".

Any help?

[GiveMeABreak]

What's your VIN?

[mighty]

VF7**************[VIN obfuscated, can be read by forum staff]**************

[GiveMeABreak]

Ok, so you have the DW8 engine and this table explains the temperature values. You don't have Air Conditioning on this model, so only a 2 speed fan.

Click to Zoom

This is the Back Up Mode:
An engine coolant temperature sensor fault leads to the following actions:

• Operation of the cooling fan at fast speed
• Switching off of the air conditioning compressor
• Display of the warning lamp STOP and of the engine coolant temperature warning lamp on the instrument panel (*)
• A message is displayed on the multifunction screen
• To record a fault in the engine ECU

So according to this if it was the coolant temperature sensor, the fan would be on full speed. So I would suspect the relay may be faulty.

Check out Fuse F4 (10A) & F8 (20 Amp) in the engine compartment Fuse Box:

And the Relays:
MF1 is the 20A - 80 Amp Cooling Fan Relay

[mighty]

Thank for your reply. I have been doing some diagnostics the last hour and have found out that the high speed relay was badly corroded and not working. The low speed relay was working fine. Does that also explain why the low speed wasn't working?

One thing that puzzles me is that there is 11v at the supply cable from high speed relay to the fan even with the relay disconnected. Where is this voltage coming from? It's no power there as it won't power anything, but still 11v.

[GiveMeABreak]

This is the control diagram. The additional power you are detecting will be from the Fan Resistance unit (not show below).

Components BSI: Built-in systems interface 0004: Instrument panel 1220: engine coolant temperature sensor 1320: Engine ECU 1510: electric cooling fan unit 7215: multifunction screen 8009: Linear pressure sensor

Connections	Single arrow: Wire connection Triple arrow: Multiplexed connection
No. of link	Signal	Nature of Signal
1	Air conditioning circuit pressure	Analogue
2	Engine coolant temperature information. Information on the engine coolant temperature alert	CAN
3	Issuing of the message: Engine water temperature warning	Comfort VAN
4	Engine coolant temperature information. Information on the engine coolant temperature alert	Comfort VAN
5	Control of the fan assembly (at mid speed only) (*)	All or nothing
6	Control of the fan assembly (normal or fast speed)	All or nothing
7	Cooling fan rotation information	All or nothing
8	Engine coolant temperature information	Analogue

(*) For vehicles with a three-speed cooling fan (fitted to vehicles with air conditioning), mid speed is controlled by the BSI. The low and high speed controls remain unchanged.

[mighty]

Still no power to the fan. When testing with lexia i get power from the low speed relay, but the high speed relay get's no signal to activate. The only power cable to the fan goes through the high speed relay.

I don't get this.


Edit:
The high speed is actually working now, but is not kicking in until 110 degrees. A bit too hot.

[GiveMeABreak]

It should be about 105 as per the table. Maybe replacing the temp sensor will rule that our for sure? - they're quite cheap to replace.

[mighty]

Both high and low speed is now working. The broken relay made the high speed not work and the broken resistor made the low speed not work. Wish i knew that before I bled the coolant serveral times and bought a new fan

Thanks for the help

[GiveMeABreak]

Well done on that and thanks for bothering to come back and update us - it's always helpful to others to find what the cause was

[xantia_v6]

Both high and low speed is now working. The broken relay made the high speed not work and the broken resistor made the low speed not work. Wish i knew that before I bled the coolant serveral times and bought a new fan

Thanks for the help

I wonder if both of those faults were caused by a fan motor drawing too much current, perhaps because of stiff bearings or debris from the brushes?

[mighty]

I don't think so. Both parts had obvious corrosion. There is a lot of salt on the roads here, about 6 months of the year.

[white exec]

Single-fan BX (one motor, one resistor, one relay) used to suffer corroded contact issues too.
Twin-fan installations (BX, XM...) ditto, this time relying on a bank of three relays to switch fans into series/parallel to provide the two speeds.
Fans vary between 105 and 310W apiece, so a lot of current involved, which just finishes off poor connections.
12v operation has a lot to answer for!

As you say, all this is "up front" and best placed for assault by salty spray.

[Loz1968]

Hello and looking at your under bonnet fuse box. My Berlingo 1.9 DW8 appears to have a different fuse layout and so does my handbook.
Fan not cutting in and needed to use fan heater in heavy traffic to cool engine.
New Radiator and fan fitted 2 months ago.
Please advise