2004 c5 hdi 110 cooling fan woes FIXED and now running (pg 6 on) .

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citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

Probably not as the plugs are sealed.. The only way to get at the pins is to unplug them..
MGmike
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by MGmike »

OK, I guess you need to take the plunge and replace the ECU...

But before you do... and to get the car running again I would fit one of these:-

https://www.carbuilder.com/uk/mini-add- ... use-holder

and connect the bullet to a switched 12v supply with a length of suitable wire. The easiest point to pick up a switched live will be the wiper feed cable which is one of the big ones on the two pin grey connector in the middle of the BSM. That will need you to strip a bit of the insulation to get a connection or disconnect the connector and plug in to the cable for now.

If you are happy to use a permanent 12v to get the car running you can pick that up on the cable bolted to the the BSM 13mm nut at front centre.
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

OK Mike...

Thankyou for your time you have spent looking at the wiring diagrams trying to sort things out.

There's a cheap ecu and bsi on ebay for 40 quid.. Which is too good to miss really.

Just out with the car.. Applying 12v to the supply wire for the pump DOES activate the pump... So the pump isn't at fault.
Last edited by citroenxm on 20 Jul 2021, 11:03, edited 1 time in total.
Hell Razor5543
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by Hell Razor5543 »

Is it possible there is an air leak in a diesel line? Maybe, with all of the work on the cooling fan you have been doing, you have knocked a fuel line? I would imagine that, once the fuel pump has primed the system, the natural engine action would then pull fuel from the tank if all of the pipes were 'tight'.
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

OK. A new chapter..

I have just applied 12v permanently to make the pump run constantly.. And I could hear the pump running too.. And started the car.. And.. Would you guess it.. Same response it stalls..

Time to get lexia on I think.
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

No I cannot see that happening there's pleanty of push in the pump.. I connected my volt meter up to read what the pump supply does.. After the engine starts the volts do climb but very slowly. So I thought.. Yea permanently put 12v in.. But no same problem engine still stalls.

Cam and crank HAVE to be in sync other wise it would not fire up so I can't see it being the crank sensor.. I'm still leaning to wards engine ecu
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

Well here's a number of interesting faults...
DSC_0082.JPG
Let's do a clear and see what happens..
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

Ooooo I can't clear them... I can read etc..

But when I goto erase faults. Lexia reports Communication problem..
MGmike
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by MGmike »

citroenxm wrote:
20 Jul 2021, 10:59
OK. A new chapter..

I have just applied 12v permanently to make the pump run constantly.. And I could hear the pump running too.. And started the car.. And.. Would you guess it.. Same response it stalls..

Time to get lexia on I think.
Interesting... how and where did you connect the 12v?
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

I put it at the supply cables at the bsm socket..

Just looking in lexia.. Fuel pressure regulator is showing a current of 2388.5mA... I think that's a bit high..

I think I'll double check the bsi fuses. Its strange lexia can't clear ecu faults
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

OK further lexia tests. I went into cooling fan actuator tests.. High speed fan good.. Cooling fan works.. Low speed fan... Different story..

The bsm buzzes and the fan doesn't work.. And I also did fuel line pressure tests.. The 3rd.piston was fine but the pressure regulator test produces exactley the same symptom as the low speed fan test..
MGmike
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by MGmike »

citroenxm wrote:
20 Jul 2021, 11:24
I put it at the supply cables at the bsm socket..
do you mean you pulled the pump fuse out and connected in to the pump side without the fuse in?
MGmike
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by MGmike »

citroenxm wrote:
20 Jul 2021, 11:31

The bsm buzzes and the fan doesn't work.. And I also did fuel line pressure tests.. The 3rd.piston was fine but the pressure regulator test produces exactley the same symptom as the low speed fan test..
That's not a big surprise as I think they are supplied by the same relay in the BSM. Put your replacement BSM in and see if the test results change.
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

Nothing changes.. All bsi fuses are OK..

So I think I must be looking at an ecu issue.. Its strange I cannot erase engine ecu faults..
citroenxm
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Re: 2004 c5 hdi 110 cooling fan woes and now not running....

Post by citroenxm »

MGmike wrote:
20 Jul 2021, 11:35
citroenxm wrote:
20 Jul 2021, 11:24
I put it at the supply cables at the bsm socket..
do you mean you pulled the pump fuse out and connected in to the pump side without the fuse in?
Yes... And out of interest I did it with the fuse in too.. And still the same..

I'm lexia you can do a supply relay test... I did this and the relay and fuel pump pulsed on off on off as normal.