P38A Moving a logic board from lowline to highline BECM

[P38DieselOwner]

Hi again everyone, so I have a spare highline BECM, but my car has a lowline BECM and was thinking of just swapping the logic board from lowline to the highline unit but have read on forums it won't work necessarily so I wanted to ask around if anybody had any luck with doing that. Both are taken from manual diesel P38, the highline is from a DSE 1996 and the lowline is from DT 1997.

 

[pwood999]

It would need all the security stuff copying into the Highline. There are places that can do the cloning. Also unless they relicate the mileage (kilometerage ?) then the Instruments or BECM will update to whichever is higher.

If you have the correct FOB(s) & EKA for the Highline, it would probably work, but the milaeage issue still exists. After you write down the new VIN, EKA, etc. you could disable EKA & Immobiliser just in case.

 

[Datatek]

No point in just swapping the board, if you are going to swap use the whole unit as the relay board on the low line will be different to the high line in that it will lack some components. As pwood999 say's you will need the FOB(s) for the high line, there will likely be a problem with the mileage, the VIN will be incorrect and you will need diagnostics to deal with the EDC immobiliser code.

 

[P38DieselOwner]

Oh thanks to both of you, I hoped that just putting my working logic board from a lowline into a highline and then putting the highline BECM with my lowline logic board in the car would do the trick, but I won't be doing all that just for front fogs.

 

[Grrrrrr]

Hi again everyone, so I have a spare highline BECM, but my car has a lowline BECM and was thinking of just swapping the logic board from lowline to the highline unit but have read on forums it won't work necessarily so I wanted to ask around if anybody had any luck with doing that. Both are taken from manual diesel P38, the highline is from a DSE 1996 and the lowline is from DT 1997.

Yes, done it. Worked fine.

 

[Grrrrrr]

Oh thanks to both of you, I hoped that just putting my working logic board from a lowline into a highline and then putting the highline BECM with my lowline logic board in the car would do the trick, but I won't be doing all that just for front fogs.

I did that. For some reason the fogs didn't work but I think it was a connector issue because I then put the logic boards back and Marty was kind enough to clone the Highline from my Lowline and we still had sone issues. Cannot remember what it was but Marty spotted it and fixed it. In theory though, plug and play.

 

[Datatek]

I did that. For some reason the fogs didn't work but I think it was a connector issue because I then put the logic boards back and Marty was kind enough to clone the Highline from my Lowline and we still had sone issues. Cannot remember what it was but Marty spotted it and fixed it. In theory though, plug and play.

Plug & play? You are joking. Diagnostics needed to sync the BECM to the EDC at the very least plus info relating the vehicle will be incorrect. and you will need the FOB's to go with the replacement BECM.

 

[P38DieselOwner]

I did that. For some reason the fogs didn't work but I think it was a connector issue because I then put the logic boards back and Marty was kind enough to clone the Highline from my Lowline and we still had sone issues. Cannot remember what it was but Marty spotted it and fixed it. In theory though, plug and play.

Hi, so if I understand correctly you have a lowline logic board in a highline BECM and it worked just by swapping the logic boards? Because I am confused as others mention the keyfob sync but I thought that the codes for the fob are in the logic board.

 

[Datatek]

Hi, so if I understand correctly you have a lowline logic board in a highline BECM and it worked just by swapping the logic boards? Because I am confused as others mention the keyfob sync but I thought that the codes for the fob are in the logic board.

FOB sync is not a problem, engine ECU to BECM needs diagnostics, there are problems with recorded mileage and VIN etc

 

[Grrrrrr]

FOB sync is not a problem, engine ECU to BECM needs diagnostics, there are problems with recorded mileage and VIN etc

They're all on the logic board aren't they? I don't recall any issues.

 

[Datatek]

They're all on the logic board aren't they? I don't recall any issues.

Maybe you have forgotten.

 

[Grrrrrr]

Maybe you have forgotten.

Quite possibly!

From memory I think the logic board holds all the information required though. The powerboard is just relays and mosfets and whatever.

 

[Datatek]

Quite possibly!

From memory I think the logic board holds all the information required though. The powerboard is just relays and mosfets and whatever.

Correct.

 

[RangeRoller dt]

I had a lot of stuff on my DT that you don’t usually have. I’m pretty sure it was a low line becm with fogs? Not sure how but all seemed OE and functional. Always guessed it was a manual/auto thing because of the cooler differences

 

[Grrrrrr]

I had a lot of stuff on my DT that you don’t usually have. I’m pretty sure it was a low line becm with fogs? Not sure how but all seemed OE and functional. Always guessed it was a manual/auto thing because of the cooler differences

Fogs not on powerboard on Lowline BECM but iirc the holes are there on the board so if you know what you are doing you could add the components. Or just setup a relay for the switch but the switch just signals the BECM and that controls the fogs - pretty sure it resets them to off when the ignition is cycled to stop you driving around with fogs on all day!

 

[P38DieselOwner]

Fogs not on powerboard on Lowline BECM but iirc the holes are there on the board so if you know what you are doing you could add the components. Or just setup a relay for the switch but the switch just signals the BECM and that controls the fogs - pretty sure it resets them to off when the ignition is cycled to stop you driving around with fogs on all day!

Wait really? I am not afraid of soldering, unless the parts are very small, so do you have any diagrams of the power circuit for fogs.

 

[Datatek]

Wait really? I am not afraid of soldering, unless the parts are very small, so do you have any diagrams of the power circuit for fogs.

There are no diagrams available that I know of for the BECM. I have never checked but the fogs may be switched by MOFETS not a relay. It would not be hard to work out what is needed but why bother? Much easier to wire the fogs in independently of the BECM.

 

[P38DieselOwner]

There are no diagrams available that I know of for the BECM. I have never checked but the fogs may be switched by MOFETS not a relay. It would not be hard to work out what is needed but why bother? Much easier to wire the fogs in independently of the BECM.

Thats true, I'll have to think about it.

 

[Grrrrrr]

Wait really? I am not afraid of soldering, unless the parts are very small, so do you have any diagrams of the power circuit for fogs.

Marty showed me but I cannot remember that far back.

He doesn't come on here anymore. Not sure if he still visits RR.net. He may well still go on here: https://rangerovers.pub/

 

[RangeRoller dt]

Data is right. Something you could easily diy with the oem switch it would make no real difference apart from keeping the becm that little bit safer with less to do/go wrong.