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Re: My XM 2.5 TD

Posted: Fri Oct 23, 2020 11:52 am
by Xoán
After disconnecting battery for a couple of minutes she started again, but failed several seconds later.

Re: My XM 2.5 TD

Posted: Fri Oct 23, 2020 3:38 pm
by Xoán
The 6.35mm hole in the pressure regulator has a conic ring inside, that is "new Magés" connection.

Correct pressure regulator for this ORGA is OEM527423, mine has OEM588684

Re: My XM 2.5 TD

Posted: Fri Oct 23, 2020 3:41 pm
by White Exec
Did you check fuse F1? Was it ok, and the contacts for it clean?

If ok, next check is the double injection relay - long brown one, on the front of the ECU box.
Contains two relays, and the brown cover is usually marked "Bitron".
Disconnect the battery first, then unplug the relay, and make sure its contacts (and the connector) are clean.
Plug and unplug a few times to help clean the contacts.
Plug in, and reconnect battery again.
Try that.

If starting doesn't improve, replace that relay.
It's still available from Citroen, and is part number is 1920.3X .
Original likely to be marked Type 240.104, but a recent replacement for me was marked Type 240.101, and branded Omron.
(Omron now own Bitron, and the new relay worked fine.)
Try that, because afterwards it gets quite complicated.

Caution! Never unplug or re-connect the main engine/injection ECU with the battery connected. Disconnect both + and - battery connections first.

Re: My XM 2.5 TD

Posted: Fri Oct 23, 2020 3:46 pm
by Xoán
Thanks, will try. I was driving when the car failed.

Re: My XM 2.5 TD

Posted: Wed Nov 04, 2020 10:07 am
by Xoán
Tried several options, finally sent the ECU to a specialist for physical immo-off. Still not starting and preheating light remains on.

Re: My XM 2.5 TD

Posted: Wed Nov 04, 2020 10:55 am
by White Exec
The pre-heating light is controlled by the pre-heater (glow-plug) relay, on the front of the battery box.
If it's an original (correct type) relay, it will be sensing the coolant temperature, via the engine ECU.

If not done already, clean up all the connections on the base (removable plug and two heavy-duty eye connectors), and open the relay up (cover unclips) and clean the main contacts inside.

Re: My XM 2.5 TD

Posted: Thu Nov 05, 2020 6:48 am
by Dieselman
Xoán wrote:
Wed Nov 04, 2020 10:07 am
Tried several options, finally sent the ECU to a specialist for physical immo-off. Still not starting and preheating light remains on.
Is the glow-plug lamp staying on a new fault, or prior to the Ecu being worked on.
The glow-plug lamp is a fault indicator.
You need to read the codes.

As already asked, have you checked the power is being fed through fuse 1 and that the double relay is functioning properly.

Is the immobiliser switching to Green?

Without those two power supplies functioning the Ecu won't receive the multiple power feeds it needs to function.
Check the Gnd connections are good.

The pump requires two power feeds to function, one to the Stop solenoid and a variable voltage to the fuel metering actuator to adjust the volume of fuel delivered.

Do you have the circuit diagram?

Re: My XM 2.5 TD

Posted: Fri Nov 06, 2020 1:04 am
by Xoán
Glow-plug lamp failed at same time the immo did. The problem was de pre-heating relay. Fuse 1 and double relay working ok. I have de circuit diagram. Finally ECU has been reverted to standard again, keypad unplugged, engine not starting. Did de 1€ burglar trick and engine started, car is again on de road. Runs fine but engine failure light is on and I think works hotter, 90ºC on the road as expected, 100ºC on slow city traffic and 110ºC at red traffic lights. Fans are working ok. At idle for 5 minutes does not go over 95ºC. I will read the codes tomorrow.

Re: My XM 2.5 TD

Posted: Fri Nov 06, 2020 6:43 am
by Dieselman
If those temperatures are with the A/c running, then probably not an issue.

It will be interesting to see what codes you have.

1e trick?

Re: My XM 2.5 TD

Posted: Fri Nov 06, 2020 7:22 am
by White Exec
Those temperatures are ok. 2.5 normally operates at just under 90C, normal open road driving, and will climb towards 100/110 if climbing uphill. The cooling system will cope easily with all this if the fans are operating correctly. Your cooling system sounds ok.

When you say the ECU "has been reverted to standard again", what was done to it earlier?