P38 4.0 SE 1997 - Unknown item - info requested!

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
P38 Monkey

P38 Monkey

Well-Known Member
Posts
638
Location
Cambridge
Just swapping my kph (Japan) speedo for an mph version, and tidying up the driver's side dash. The wiring has been hacked about a lot... The Valeo box in the photos was fixed in using cable ties. It seems to be some sort of motor, connected into the main loom, but the drive output is not connected to anything. Just wondering what it is, and can I just disconnect it..? Connector in last photo.
under dash 1.jpg
under dash 2.jpg
under dash 3.jpg
under dash 4.jpg
As ever, your expert help would be greatly appreciated...
 
Ah yes - I think I can see where its should go - the central heater unit has adhesive foam sheet wrapped around it and covering the right hand (drivers side) hole.
Now I have to work out why the previous owner did that...! Or I might just leave it where it is: "if it ain't broke..etc.
Many thanks for that instant response.
 
Another question on this project: is a replacement instrument module (mph) simply plug and play? Or does the replacement unit need synchronising to the BeCM in some way?
 
P38 Monkey said:
Another question on this project: is a replacement instrument module (mph) simply plug and play? Or does the replacement unit need synchronising to the BeCM in some way?
Click to expand...
To answer my own question - seems that I'll get an "Odometer Error" message. Clearing it with a Nanocom or whatever will presumably leave the mileage displayed at the higher of the two figures. I plan to get an instrument cluster off eBay and swap the central plate over. Russian roulette on removing the needles with the old "2 teaspoons" method. Of course the odometer will still be in km and no doubt the consumption info will be in litres per 100 km, but that does not concern me.
Any further advice as ever greatly appreciated...
 
I would be very careful plugging it in “Willy nilly” it will take the numbers from the highest so if you have 200k KLMs then it could show as Miles:).

Shame Marty. Isn’t around:( but if you speak to Callrova (Rick) he will sort it but you may have to send him the Cluster and BECM, but it would work and be right;).

J
 
marjon said:
I would be very careful plugging it in “Willy nilly” it will take the numbers from the highest so if you have 200k KLMs then it could show as Miles:).
Shame Marty. Isn’t around:( but if you speak to Callrova (Rick) he will sort it but you may have to send him the Cluster and BECM, but it would work and be right;).
J
Click to expand...
Thanks - that's good advice. I am planning to simply swap the central (tacho+speedo) back plate on my existing module, so it should just work the same as before but with mph markings under the speedo needle.
I have checked, and the effective conversion is OK. I probably should not have started this mini-project but it's too late to backtrack now...
 
P38 Monkey said:
Thanks - that's good advice. I am planning to simply swap the central (tacho+speedo) back plate on my existing module, so it should just work the same as before but with mph markings under the speedo needle.
I have checked, and the effective conversion is OK. I probably should not have started this mini-project but it's too late to backtrack now...
Click to expand...

Not quite sure what you mean by swapping (pics)

“so it should”:eek: it’s a P38 so don’t assume that:). Not researched so you maybe right, so keep us posted:).

J
 
Even just plugging a different cluster in to check things will mess up the mileage, i did it with mine and gained 30k on the counter:(
if all you are doing is swapping the face with the markings then should be ok ,or as mentioned send it to callrover.
 
brianp38dse said:
Even just plugging a different cluster in to check things will mess up the mileage, i did it with mine and gained 30k on the counter:(
if all you are doing is swapping the face with the markings then should be ok ,or as mentioned send it to callrover.
Click to expand...
As above, the mileage will go to the higher figure. I think you need to tell the BECM that it's either Km or Miles.
 
Grrrrrr said:
I am pretty sure you can change the kph to mph using diag. Not sure on Nanofom but definitely on Faultmate.
Click to expand...
The issue is that the speedo is printed in km/h. Hard printed, in paint. Fixed numerals and divisions in km/h. It's a dial, not an LCD.
There are issues about the BeCM synchronising with the odometer if you simply switch the whole instrument module - see postings above.
No doubt you can change the fuel consumption reading from litres per 100 km, to mpg, but who cares.
I am planning to switch just the relevant passive components: stepper motors and needles / backplate assembly. I hope that the speedo will move the needle by the same speed/angle rate as before, only now it will be hovering over mph figures on the dial.
So what could possibly go wrong?
Being a P38, the answer to that question is "A lot". "Unknown item in bagging area...!!" (You need to say that last phrase in a Dalek voice).
 
Last edited:
P38 Monkey said:
The issue is that the speedo is printed in km/h. Hard printed, in paint. Fixed numerals and divisions in km/h. It's a dial, not an LCD.
There are issues about the BeCM synchronising with the odometer if you simply switch the whole instrument module - see postings above.
No doubt you can change the fuel consumption reading from litres per 100 km, to mpg, but who cares.
I am planning to switch just the relevant passive components: stepper motors and needles / backplate assembly. I hope that the speedo will move the needle by the same speed/angle rate as before, only now it will be hovering over mph figures on the dial.
So what could possibly go wrong?
Being a P38, the answer to that question is "A lot". "Unknown item in bagging area...!!" (You need to say that last phrase in a Dalek voice).
Click to expand...
I think you will find that the needle calibration is different. I have one with MPH and one with KPH and 30mph is not in exactly the same place as 50kph.
I think that if you change KPH to MPH in the BECM that the kilometers logged will become miles logged so showing a false reading, I have never had the courage to try it but as far as I can see, there is no facility in the BECM to do the maths to make the conversion as it is not something that is needed.
I actually do not see the problem, I run an mph speedo in Europe and have no problem remembering the speed limits in mph. For my wife, I use an app called DigiHud to display the speed in kph on her phone
 
Datatek said:
I think you will find that the needle calibration is different. I have one with MPH and one with KPH and 30mph is not in exactly the same place as 50kph.
I think that if you change KPH to MPH in the BECM that the kilometers logged will become miles logged so showing a false reading, I have never had the courage to try it but as far as I can see, there is no facility in the BECM to do the maths to make the conversion as it is not something that is needed.
I actually do not see the problem, I run an mph speedo in Europe and have no problem remembering the speed limits in mph. For my wife, I use an app called DigiHud to display the speed in kph on her phone
Click to expand...
As ever, very valid. In retrospect I should not have started to make this km/h to mph conversion, but now might as well follow through. Just waiting for my mph eBay instrument module to make its way through the Royal Mail strikes etc.
I was reworking the panels around the steering anyway, as they are all damaged. The previous (Japanese) owner had fitted a lot of inscrutable electronic devices, hacked the wiring about, and seriously damaged every single trim panel. I think they must have been using an LR Series toolkit (mole grips, monkey wrench, ball pein hammer).
The tyres on my P38 are oversize, so the speedo will probably have a 5% or so error one way (under reading the speed), and whatever JLR designed the other way (over reading)..
Then there's what the BeCM and the speedo discuss between themselves, and agree the speed to actually be displayed.
I'll have to see what the calibration looks like when I have installed it and if necessary just go back to km/h...as ever, learning more about my P38 every day.
 
You must log in or register to reply here.

Similar threads

Dr_evil
Series King Cab
61 62 63
Replies
1K
Views
127K
discomark10
discomark10
Back
Top