citroen xantia xu10jp4 ecu electric harness

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saeedm
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citroen xantia xu10jp4 ecu electric harness

Post by saeedm »

hi there.
i dont know that where i have to connect these yellow-green line wires!
they are the wires that are near oxygen sensor connector and feeding ecu +12 but where are they connected?
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wheeler
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Re: citroen xantia xu10jp4 ecu electric harness

Post by wheeler »

They are earths so its shouldnt really matter to much as long its a good clean earth. If its the ones im thinking of though the bolt straight onto the top of the gearbox.
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saeedm
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Re: citroen xantia xu10jp4 ecu electric harness

Post by saeedm »

yes i did that too. but car wont start and also ecu was not working(not connecting to diagbox and no check engine light + no crank on dashboard) then i checked the ecu input voltage i mean pin 18 on ecu connector. it was negative 12 volt while it have to be 12+
then i followed the wire of pin 18. it is ended on those yellow-green line wires so should i connect them to positive?
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xantia_v6
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Re: citroen xantia xu10jp4 ecu electric harness

Post by xantia_v6 »

Do not connect those terminals to +12V, it will destroy the ECU!

I think that you may have counted the pin numbers incorrectly on the connector.

Is this the original harness and ECU for the car?

I think that the XU10JP4 may have been fitted with more than one type of ECU that would require a different harness. If you post the VIN, we may be able to work out what should be fitted and find a correct wiring diagram.
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saeedm
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Re: citroen xantia xu10jp4 ecu electric harness

Post by saeedm »

the harness is looking like the original of the car
ecu is bosch mp5.2 and i know it is the original of the car (but ex-owner turned immo off)
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pin 18 on ecu marked with red
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car VIN:
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saeedm
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Re: citroen xantia xu10jp4 ecu electric harness

Post by saeedm »

guys can u help me?
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saeedm
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Re: citroen xantia xu10jp4 ecu electric harness

Post by saeedm »

thank you all for help.
i checked the ecu connector again and found that i counted the pins incorrectly. the pin that i was thinking it is 18, in fact was pin 2. and i connect the yellow-green line wires to ground on gearbox as like it was before.
but there wasn't any voltage in pin 18. so i checked fuses(f6 inside cabin and big fuses under hood) and they all had 12+ voltage.
so finally i followed the wire of pin 18 to find problem.
and i found it.
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