Replacing AL4 transmission ECU

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Haakon
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Replacing AL4 transmission ECU

Post by Haakon »

Having seen my ECU see a solenoid short to positive that doesnt exist and then ask for 22BAR of line pressure, I fairly confident its stupid and has a poor grasp on reality.

So am trying to replace it.

I was of the understanding they're plug and play - its only the engine ecu/BSi that are coded to each other - anyone know different?

Also, ASV auto parts said they had my ECU (S118047502C) but sent me another one (S118047526C, which they say is in all the Xsara2 they have wrecked)- which booted straight into limp and locked out the immobiliser Now they say my number is a new universal part that dealers supply thats not original to my car and anything they supply needs to be coded. Not sure whats going on here...

Also tried a Renault Scenic ecu i found at pinchapart for $25 - it booted into limp and I couldnt even communicate with it via Lexia.

Cant see anything in lexia about coding beyond the standard parameters resetting thing.

Any clues? Really dont want to go back to the dealer...

The holy grail is of course the whole software on a CD that can be reloaded onto a wiped ECU offline...
Haakon
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Re: Replacing AL4 transmission ECU

Post by Haakon »

No clues? Anyone ever had a transmission ecu changed?
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DickieG
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Re: Replacing AL4 transmission ECU

Post by DickieG »

What car is this for?

IIRC when this transmission is fitted to Xantia's there is a procedure to re-initialise the ECU to allow it to relearn the throttle position plus there is a service counter that needs resetting when the fluid is changed so I'm wondering whether these two issue may have an effect on what's happening to the original ECU.
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Haakon
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Joined: 18 Feb 2011, 12:39
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Re: Replacing AL4 transmission ECU

Post by Haakon »

Xsara 2 multiplex with an EW10 motor.

Tried the reinitialisation, but no effect.
wheeler
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Re: Replacing AL4 transmission ECU

Post by wheeler »

The auto box ECU is definitely not coded to the injection ECU or BSI & a second hand one can be used no problem.
Only thing you need to do as dickie G says is reset the oil wear counder & re calibrate the throttle position sensor.
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