Cooling fan ?

[Stevo83]

I have problems with my 67 berlingo bluehdi. Triangle on and in limp mode. P0480 relating to radiator fan. It appears to be running slow speed all the time. I have changed the relay for a new one and checked wiring to bsi. Still the same. Any1 any ideas. Thanks.

[Sol]

Hi,

The two speed cooling fan module (not the relay) is mounted on the front upper left of the radiator itself. This could be faulty. The relay only supplies the main power via F21 in the engine bay fusebox, so if low speed works and especially when running by itself, the relay cannot be faulty. No fan speeds at all, then perhaps, yes or fuse F21.

Remember the BSI is a full blown computer, so the wiring to and from it, is not the only thing which can cause a problem. It is the MAIN ECU for anything (all things) non engine related, but the engine ECU (1320) is in control of all engine-related functions, including the dual speed cooling fan (controller is 1522, fan is 1510).

Attached:

Component ID codes for schematics
B9 Fan control unit location
B9 Engine Cooling circuit

Also P0480 does not exist in Citroen systems, is this an aftermarket OBD reader code you pulled? They are not always reliable on a PSA vehicle. the nearest code is:

P0483 Cooling integrated into the ECU function (fan unit) : Open circuit

Or

P0494 Cooling integrated into the ECU function (fan unit) : Coherence between cooling fan fast speed and the reference

P0495 Cooling Function Integrated into the ECU (fan unit) : Coherence problem

[Stevo83]

My bad it was the module on the radiator I replaced. I read the codes with a hella and autel.

[Sol]

Ok so see the attached zoomed in snip, the ECU uses ground control like a horn circuit does (ground the correct pin to select high speed or low speed)

At the fan controller:
Plug 4V NR (4 pin Black)
Pin 1 - 1540P - Fan control 1 (-) High Speed (connect to GND to operate with ignition ON)
Pin 3 - 1590A - Fan unit Relay power supply (from F21 / Relay R1)
Pin 4 - 1559P - Fan unit Diagnostic feedback
Pin 2 - 1550P - Fan control 2 (-) Low Speed (connect to GND to operate with ignition ON)

Plug 2V GR (2 pin grey)
Pin 1 - 1514A - Main fan control (out to fan motor)
Pin 2 - BM05A - main battery fusebox +

So pin 2 (4V NR) could be shorted to GND on the controller or at the ECU or at the wiring harness, this would make the fan run in slow speed at all times. Or your ECU is faulty.

Normally an Autel Maxi ECU / 808 is pretty good as a PSA code reader, not sure why it's getting this code which I can't find in the official lists. The little Autel ones are not so good on these cars.