Xantia - Fuel pump question , car wont start

[lancia58]

Hi

My Xantia want start, checked the fuel pump and notice that there is no fuel flow. I checked the terminals of the fuel pump connector while the car switch is on and can not read 12v on any of the terminals. My question is when the switch is on one of the terminals should be a constant 12v ?
I had this problem 2 weeks ago and my friend that is a mechanics hit with a screw drive on the fuel pump and suddenly there was a fuel flow and the car started. I don't know if the pump is clogged or when he hit on the pump by chance the 12v was back.
I also pushed this red button ( emergency fuel cut ) under the hood but it didn't help. Is that button normally open or closed ?
I suspect that the pump's 12v is missing. Any ideas how to track it?

Thanks
Zohar

[CitroJim]

Petrol Xantia pumps rarely fail Zohar but diesel ones do!

The pump will run briefly at ignition on/immobiliser off to prime the fuel rail and then only run again when the engine is running... The pump will not run if the engine is not running except for the brief initial prime as described...

If the pump is good you will hear a low him from it on ignition on...

Use a voltmeter to check for power at the pump. Easily accessible via the large plastic cover right under the RH rear seat.

[lancia58]

Hi Jim

Do you know how long is the priming? As long as the priming is active one of the four terminals of the fuel pump connector should be 12v do you know which of them? I oppend the fuel pump cover under the back seet and the connetor has four wires. Two yellow one thin white wire and one thick white wite.

Thanks
Zohar

[CitroJim]

It's about 3 to 5 seconds Zohar...

The pump supply is on the two thick wires....

[lancia58]

Hi Jim

Thanks for the valuable info. Do you know where is the fuel pump relay ?

Thanks
Zohar

[CitroJim]

It's one half of the big double-injection relay down by the Engine ECU Zohar...

The other half supplies the ignition coil...

The relay is operated from the ECU via the immobiliser.

They rarely fail...

[lancia58]

Thanks Jim,

Is it the Bitron relay located in the box the ECU is in ? If so when turning the switch on without spinning the starter I can feel/hear a click and than after 2 to 5 seconds ( priming time ) another click? Which terminal of the Bitron relay is applied with 12v to close the relay that fed the 12v to the fuel pump ?

Thanks
Zohar

[CitroJim]

Yes, if the relay is big and rectangular rather than square that'll be it!

If it clicks on and then off after five seconds all sounds good...

Look at the wiring diagram I sent you the other day for which pins on the relay do what... It should be fairly clear... identify the pump on the wiring diagram and work back, via the fuse and possibly the inertia switch (the one that will cut the fuel in case of an accident) and the relay...

[lancia58]

The inertia switch is the one with RED button under the hood ? Is it normally open or closed ?

Thanks
Zohar

[CitroJim]

That's the one Zohar. Normally closed..

It's well worth trying to reset it by pressing on the red button...

Just in case it's tripped...

[lancia58]

I pushed it couple of times. Just notice that the connector that is hooked to it is secured with a plastic tie. I'll try to unplug it and spray it with electric contact cleaner. As it gets warmer I was able to turn on the car. It may be related to the problem I think I have with the fuse box under the steering I described in the topic http://www.frenchcarforum.co.uk/forum/v ... =3&t=53866. I'll start with the inertial switch connector. The fuse box is a tough one as it doesn't have connectors. I suspect it for a long time. I took apart the same fuse box I detached from a 2001 Berlingo, and at least I have the understanding how to do the job, it is a couple of hours task, remove all terminals of the fuse box one by one and hooked them to the fuse book I detached from the Berlingo.

When I have the problem I described in the topic http://www.frenchcarforum.co.uk/forum/v ... =3&t=53866 , the red icon of the open door in the instrument cluster is blinking and I can hear a relay that is clicking. It looks like that clicking relay is some where behind the center air vents in the dash board. I tried to locate this relay but still didn't. If you have any clue regarding where is this relay it may be a good lead to sort the fuse box topic and the fuel pump cut I think these problems are related

Thanks
Zohar

[lancia58]

Hi

It did was the fuel pump, the pump motor is not functioning . I replaced the whole pump with a new one .

Thanks
Zohar

[CitroJim]

Pleased to hear all is now good Zohar

[lancia58]

Thanks Jim. Just to emphasize when it first happened ( April 2016 ) hitting the pump with a wrench sort it up till now. It happened again two weeks ago and the only temporary cure was to feed the pump with external power source in reverse polarity i.e. the source + to the pump's - and the source - to the pump's +, causing the motor to spin backwards. After doing that and plugging the pump's connector I was able to drive the car home, but after turning the car off the pump wouldn't start again. So it was parking for two weeks until the pump I bought out of eBay arrived.

Regards
Zohar

[ozrkr]

I realise this is a very old string now. I hope the people involved (lancia58 and CitroJim, mainly) are still interested ...

For a long time (many, many months), I have been chasing a problem just as you describe on my 2000 Xantia 2.0L petrol namely:
- on cold mornings (sub 12 degrees or so), when I open the door to start the car,
- the red "door open" indicator flashes
- I hear a relay clicking in sync with the "door open" indicator. The relay clicking **appears** to be coming from the Body Computer, which is attached to the heater, behind the glovebox (RHD car)
- the starter turns over (strong battery) but the car does not start. I'm not sure, but it is as if there is no fuel supply to the injectors ...
- if I run a fan heater in the cabin for around an hour, aimed at the Body Computer, the car starts as per normal

In my deliberations, I have swapped out the passenger compartment fuse box (which is as per xf1ref's picture) with a spare unit. That made no difference to the behaviour. However, I didn't try to check the wiring to the fuse box ...

Can you advise what your final conclusions, please? What did you do that fixed the problem?

And while you're about it, please advise the location of:
- the ignition ECU and
- the Bitron relay

I must say, this all shows the value of this forum! (as if there was any doubt!) The fact that in 2024, I can stumble across postings from 2015 that precisely describe my problem is remarkable!

I would appreciate any advice you can give me.

Regards,

Kim