P38A KPH to MPH

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Interesting.
UK manual doesn't give it one way or the other, but as you say it's clearly stated as a Major in the NI one.
UK here. Section 7.8
www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/7-other-equipment

It's not a fail in England, or at least it didn't use to be
I always assumed that MoT requirements were the same across the whole UK. You live and learn. I wonder what other differences there are.
 
I always assumed that MoT requirements were the same across the whole UK. You live and learn. I wonder what other differences there are.

In Northern Ireland their politicians have stopped even pretending to work yet still get laid. Scotland gets a remarkable amount of money per capita and Wales is f@cked.
 
In a previous life, I was involved with jap imports. Mostly bikes. In the 90s, we used to add stickers to the speedo outer glass, also changing the label to mph. The speedo was not tested (for mot) but had to be in mph and lit.

Later, for the mechanical speedo, you purchased a gearbox to convert mph to kmh. Then you only needed to over label kmh with mph.

After that, there were various devices for electronic speedo. These things changed the pulse frequency ‐ in those days bikes did not have abs. These devices were popular in cars as you could correct the speedo when fitting your Carlos Fandango wheels.

On canbus systems, the same variable may be used for safety and systems in addition to the speedo. A conversion may be an opamp circuit between the needle wiring and the dc input. Means you could drive at 48mph on the bump stops instead of 30mph :)

If someone is offering to convert yours, that sounds like the best solution.
 
Good to know things move on. In my day, you had to have a speedo, it had to be labelled mph and it had to be lit when lights were on.

There was no requirement for it to accurate or work (that came under construction and use).

We were able to mot simply by over marking the k (in kmh) with an 'm'. That was it
 
the only requirement is for a speedo to work, if its fitted. no speedo, no problem. what it shows doesn't matter as thats not part of the MOT, therefore could be calibrated to any measurement of distance over time. accuracy is not tested
https://www.gov.uk/guidance/mot-ins...d-light-commercial-vehicles/7-other-equipment
I think if you look a bit deeper, any vehicle capable of more than about 30mph is required to have a speed indicator. In the past even a rev counter was acceptable if the critical speeds for each gear were marked.
 
Hi
New to the forum so if I'm being dumb feel free to shot me down in flames..
I've bought an import P38 (4.6 Gems) and want to change the speedo face to MPH from Km/hr.
Not really bothered about the odometer reading Km.
My thoughts, and this might be me being dim, the speedo and tacho gauges (along with the other two), are just magnetic volt meters. Is there any reason why the tacho and speedo "meters" cannot be taken from an "MPH" binnacle and fitted to my existing one. I appreciate there may be marginal calibration differences but I'm kind of guessing the manufacturing tolerances will be reasonable and both the Km/hr and MPH will have the same FSD.
Anybody tried this?
 
Hi
New to the forum so if I'm being dumb feel free to shot me down in flames..
I've bought an import P38 (4.6 Gems) and want to change the speedo face to MPH from Km/hr.
Not really bothered about the odometer reading Km.
My thoughts, and this might be me being dim, the speedo and tacho gauges (along with the other two), are just magnetic volt meters. Is there any reason why the tacho and speedo "meters" cannot be taken from an "MPH" binnacle and fitted to my existing one. I appreciate there may be marginal calibration differences but I'm kind of guessing the manufacturing tolerances will be reasonable and both the Km/hr and MPH will have the same FSD.
Anybody tried this?
The speedo face on one of mine has KPH & MPH. You sure they are just volt meters?, I thought they were a bit more sophisticated than that.
You can swap from KPH & MPH in the BECM, so if you swap the instrument head, change the setting in the BCM to match. Do not try to change the whole instrument panel unless you are aware that if you do, the logged mileage will default to which ever is the higher, the replacement instrument panel or the BECM.
 
Not certain but the options would be that or stepper motors. I'm going on the info I gleaned from this video:-

No personal knowledge but this looked like an easy way out if it'll work. Would only be the actual gauges that I'd swap.
(Have to be both the tacho and speedo as the heads are the one unit).
 
I changed my Japanese km speedometer to mph but left the odometer in km so as not to confuse the BeCM. I got a cheap but good UK instrument module for about £30 and just swapped all 4 instruments across. Easy to do as the connectors are in the fixing screws. Was a doddle, and works fine now.
 
Hi P38 Monkey.
That was my plan (mines is a Japanese import). In my case I don't see any point in swapping the "temp" and "fuel" gauges as the assembly I've bought will have a much higher mileage than the 57K on mine but it looks like a simple case of unclipping the front, removing the six screws and lifting the tacho/speedo out.
I'm in the process of setting up a laptop and going to buy RSWsolution's software so I'll wait till I've got that before I bugger about with anything electrical in case it all goes wrong.
Thanks for the replies and the info, much appreciated and I'll update once I've done it.
Cheers.
 
Hi P38 Monkey.
That was my plan (mines is a Japanese import). In my case I don't see any point in swapping the "temp" and "fuel" gauges as the assembly I've bought will have a much higher mileage than the 57K on mine but it looks like a simple case of unclipping the front, removing the six screws and lifting the tacho/speedo out.
I'm in the process of setting up a laptop and going to buy RSWsolution's software so I'll wait till I've got that before I bugger about with anything electrical in case it all goes wrong.
Thanks for the replies and the info, much appreciated and I'll update once I've done it.
Cheers.
I changed all 4 instruments so they matched. Easy job. Odometer is in km but I did not have to do any risky programming…
 
The instruments I've bought matches so easier still. I don't have an EKA code or a working fob for the car and I'm not sure about getting one from my local LR dealer with it being a Japanese import so I'm loathed to disconnect the battery in case I get the dreaded "engine disabled". The RSW SW will read the EKA code so that'd give me a starting point. I know the dealer has ran the battery flat and it's been swapped to no ill effect but just in case .......

Thanks again
 
The instruments I've bought matches so easier still. I don't have an EKA code or a working fob for the car and I'm not sure about getting one from my local LR dealer with it being a Japanese import so I'm loathed to disconnect the battery in case I get the dreaded "engine disabled". The RSW SW will read the EKA code so that'd give me a starting point. I know the dealer has ran the battery flat and it's been swapped to no ill effect but just in case .......

Thanks again
The RSW software may not read the EKA code. The best option is to turn off EKA and the immobiliser.
 
The instruments I've bought matches so easier still. I don't have an EKA code or a working fob for the car and I'm not sure about getting one from my local LR dealer with it being a Japanese import so I'm loathed to disconnect the battery in case I get the dreaded "engine disabled". The RSW SW will read the EKA code so that'd give me a starting point. I know the dealer has ran the battery flat and it's been swapped to no ill effect but just in case .......

Thanks again

A main dealer should be able to tell you the EKA. It may be the NAS default which I think was 1515.

The speed and mileage comes from the BECM via the ABS module. It averages the pulses from the 4 wheels. BECM can be switched between mph and kph but I have a feeling if you convert to kph the mileage jumps up and the binnacle takes the mileage but if you put the BECM back to mph the BECM initials drops but then is overwritten by the higher number in the odometer (which has no units). I'm pretty sure someone came up with a hack around this (maybe zeroing something first?) but I cannot recall what they did.
 
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The best option is to turn off EKA and the immobiliser.
Thanks for the response.
This is the ultimate plan once I've got a way to "talk to the car". Then I'll be searching for a "blow by blow"
A main dealer should be able to tell you the EKA. It may be the NAS default which I think was 1515.

The speed and mileage comes from the BECM via the ABS module. It averages the pulses from the 4 wheels. BECM can be switched between mph and kph but I have a feeling if you convert to kph the mileage jumps up and the binnacle takes the mileage but if you put the BECM back to mph the BECM initials drops but then is overwritten by the higher number in the odometer (which has no units). I'm pretty sure someone came up with a hack around this (maybe zeroing something first?) but I cannot recall what they did.
I'm not that fussed about the the units on the Odometer. If it was easy to change I would have given it a go but it seems a bit of a minefield so I'll live with "Kilometers" The speedo looks like an easy fix just swapping over the tacho and speedo meters from the MPH binnacle. Fingers crossed,
.
 
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