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I put an MF31-750 on a boat with 4.3 litre inboard motor that is in bits so cannot be run to charge it. I've been working on other stuff on the boat like the hydraulic tilt and trim, various sensors and lights. The battery is still fine even though it hasn't been charged since the day it was delivered.

Couldn't tell you what the voltage is as I've never bothered checking but they are fully charged. Just bolt it in and use it.

???

There was mention of this really helpful quirk of the EAS diagnostic system in another thread recently (this one https://rangerovers.pub/topic/2698-dead-eas?page=1) but I think I might have found what is means.

I've been on the other side of the Channel (again) and just put another 2,000 miles on the clock. Arrived at my mate's house on Saturday and was leaving Sunday morning. As I was towing, the EAS was locked in Motorway as I normally keep it, but his 'driveway' needed a bit more clearance so turned inhibit off and poked the rocker to put it to Standard height. Up she came and I set off, only to notice the EAS light on the dash had come on and it was at High. Thinking I might have poked the rocker twice, I sent it back to Standard and carried on. About a mile later, the dash light comes on again and it rises to High, poke the rocker again and drop it down to Standard. By this time I'm trying to remember where the spare rocker I have somewhere might be as it looks like mine is showing it's age. Then, just as I was going through a toll booth, it does it again. As I'm travelling slowly, I ignore it for a minute and that was when it gives me the beeps, 35MPH MAX and drops me to the bumpstops. Pulled over, got the Nano out, checked the fault and there it was, Invalid Fault Code. Cleared the fault, everything went back to normal and I carried on, leaving the Nano plugged in so I could clear it while driving if it did it again. Which it didn't.

Then I drove through the sort of rain I have only ever found in France. Hammering it down, motorway traffic down to 40 mph, wipers on high speed, road surface with about 2 inches of standing water, spray everywhere. That cleared and I carried on for another half hour or so when again, it decided it was going to go to High without being told to (was locked in Motorway at the time too). Cleared the fault, carried on only for it to do it again a couple of minutes later, dropping me to the bumpstops again too. Cleared the fault (Invalid Fault Code again) and, just like the previous time, it didn't do it again.

Then I started pondering it and realised it had only done it after torrential rain. The previous afternoon, on my way to my mate's house, I'd driven through this......

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Which had subsequently turned to rain as I'd dropped down off the mountains. The car had then stood overnight and had started doing it as soon as I'd started it up for the journey home. Having the heater on to keep me warm may well have dried out any moisture that had managed to find it's way into the car. Then it had done it again after driving through more heavy rain. We all know that the multiway plug behind the RH kick panel can corrode and cause silly problems, but the wiring between the EAS ECU under the drivers seat and the rocker switch, runs through a near identical one behind the LH kick panel. I bypassed the RH one years ago but had never even looked at the LH one. So, having got home a few hours ago, I just have. I suspect Invalid Fault Code is caused by corrosion in the plug on the LH side as this is what I have found.

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Pins and sockets look good, not rotted away completely like some I've seen, and should clean up easily enough, so that is a job for the morning but I'll put a bit of silicone grease in there to protect them from any moisture in the future. It seems to be dry in there but I don't believe in coincidences and the green isn't going to help at all. As Bolt discovered some time ago, the rocker isn't just a switch, it has some electronics in there too so I'm thinking a high resistance connection between different pins would be enough to make the ECU think the rocker had been pressed. If it sees signals that suggest the rocker is being pressed up and down simultaneously, that may well be what triggers the fault.

Aspirator probably just needs years of accumulated dust cleaning off it. Squirting cleaning stuff through the little grille doesn't usually work though, it needs to be taken out to do it properly. That will be why it is blowing only warm air as it thinks the interior is already up to temperature. Mine blows air out of the vents initially then, as the interior of the car warms up, it blows onto my feet. Maybe yours is doing the same but blowing cooler air as it thinks the interior is warmer than it really is and doesn't need any more heat?

BeCM doesn't send a signal to immobilise, it just doesn't send the mobilise signal when you unlock the car if it thinks the car needs to be immobilised. Hence no check engine light as the ECU doesn't power up without getting the signal. Admittedly, on a European car, that is about the only function of the Check Engine light, to tell you the ECU is powered, it doesn't come on when the wind changes like on your NAS car.

@harv, there's no downstream sensors on rest of world spec cars, only NAS.

I've not known them cause really bad running, but I do know if you run a GEMS with the lambda sensors disconnected, the ECU progressively weakens the mixture until it won't run at all. GEMS uses 5-0V sensors with 0V being rich, whereas Thor uses 0-1V sensors with 0V being lean so it could be richening the mixture sufficient for it to run badly. Although with a multipoint slave LPG system, it would run badly on LPG too.

Level must be checked with a cold engine, engine running and after cycling through all the gears. Checking it without the engine running will show a level that is a good 100mm above the max mark.

The link posted is for a Thor. It's the cylindrical thing with 2 pipes that bypass the throttle body.

+1 on the MF31 series. I've got an MF31-1000 on both P38s and an MF31-750 on a boat. Never had a flat battery or problem with any of them.

Looks like the come with the rails and aren't available as a separate part. Rails are NLA.

If you mean the whole dashboard, follow the guide that David H posted. If you just want to remove the instrument cluster, as the other David says, it's a 5 minute job.

A dead accumulator will only cause the warning lights to come on when you hit the brakes. It stores pressure in a sphere with a diaphragm across the centre with Nitrogen at high pressure behind it. Over a period the Nitrogen leaks out so you have no stored pressure, hence the pump has to cut in to raise the pressure as soon as you use the brakes. You can't turn those lights off with the Nanocom, or, if you can, they will come straight back as soon as you use the brakes again.

My point about the EDC licence is that you've got a licence for your engine type and a second one for the other P38 subsystems but it will only show systems that you actually have. Hence no mention of Wabco D if you have a GEMS licence as the GEMS never had the D system, but as the diesel is the same licence for all years it gives you the option of either depending on the year of the car. However, the ABS document from BBS tells you which you will have from the year of the car.

It certainly sounds like you have an iffy connection to one of the sensors. They have plugs that should be held in clips on the chassis, but they are a bit of a bugger to get to as they are behind the inner wheelarch liner. If anyone has ever been in there before it is quite possible they didn't put them back into the clips so the cable could have chaffed against something. Sounds like you've got similar weather to here, far too cold to be outside laying on the ground under the car. I've got an ABS Fault/Traction Failure error on the Ascot but just ignore it for the moment. The brakes work, it's only the ABS and traction control that won't.

Answering your question on the dark side, on the BBS website there is a separate document for each system with what readings you should expect to see. EDC (diesel) is a bit odd as there is only the one entry. With a Nanocom licensed for a V8, if you have a GEMS licence, the only option you have for ABS is Wabco C as all GEMS cars used the C system, while a unit licensed for Motronic (Thor) will only show you the Wabco D option, you'd never see both and have to choose which one.

Wabco C up to 1998 model, Wabco D from 1999 onwards. Go into that and the top button is marked Faults, tap that and Read Faults, read what it is, then tap Clear Faults. If it comes straight back, then it is permanent. Beware though, the Nanocom ABS function can get it's left and right mixed up so if it says left sensor open circuit (or left sensor short to ground) it may actually be the right sensor.

That would also explain why people have said the ride improves with new air springs. New ones will have nice supple rubber compared with older ones where the rubber has started to harden with age so will flex less. Same with the Arnotts which, from the one time I have ever seen them, they appear to be thinner so will flex more, giving a softer ride when extended.

Now that is what I thought, the ride gets firmer the lower the height, although others seem to think it is the other way round?

Mine, with the 2 pin sensor, also reads differently to how I would expect it to. It has always sat very slightly above vertical, suggesting the temperature is higher than the Nanocom (and two other generic OBD readers) tell me it actually is. My sensor died so I kept the Nano plugged in to keep an eye on the temperature only to find that it runs very cool, around 85 degrees C. As they are no longer available, I got a second hand one from a breaker and fitted that. Initially it read below the centre point, exactly where I would expect it to be with the lower running temperature. Over a period though it has crept up and now sits where it always used to, very slightly higher than vertical. On a long downhill when the temperature would drop, it does, but under normal running, it stays just above what would be considered as normal despite the actual temperature being below normal. Considering the analogue voltage from the sensor doesn't drive the gauge directly, but reports to the BeCM which sends a data stream to the instrument cluster which then converts it back to an analogue signal to drive the gauge, I suspect there is some sort of adjustment going on so the gauge reads normal irrespective of actual running temperature.

It isn't often I sit and ponder why something works the way it does, I tend to concern myself with how it works and how to fix it when it doesn't, but this exchange had me intrigued so I've just been doing some sums out of interest.

Unladen weight on the rear axle with the car at kerb weight, is around a tonne (varying slightly depending on whether, petrol or diesel, manual or auto), so, as we normally measure pressure in pounds per square inch, we know the number of pounds. Without actually measuring one, I'd estimate the interior diameter of a rear air spring as around 6 inches so to convert that to square inches we multiply by Pi, giving a cross sectional area of 18.85 square inches. 1 tonne is 2204 pounds, so assuming that would be equally spread from one side to the other, meaning 1102 pounds on 18.85 square inches, or 58.4 psi.

Maximum axle weight when fully loaded is 1840 kg, or 4056 pounds, so that would give 2028 pounds on 18.85 square inches, or 107.6 psi.

In neither case is the height relevant, it won't change no matter how high or low the suspension is, the weight and cross sectional area of the air spring will still be the same. It also explains why the system pressure switch operates at 140 psi to switch off the compressor. Unless the car is grossly overloaded, there will always be sufficient pressure available to deal with the weight. This also explains why my 5.6 bar (81 psi) tyre inflation compressor was only just capable of causing my suspension to lift. Doing the sums backwards means 81 psi would be capable of holding up 1530 pounds, ample if the car was completely empty but not enough to lift it had it been fully loaded. Considering my boot carries an LPG tank in addition to a spare wheel, my toolbox, 2 tonne trolley jack, the assorted spares that live in there and it also had 3 people and one persons luggage, I suspect the rear axle weight would have been pretty close to that so right on the limit of what the pump was capable of.

What I can't get my head around is the effect the piston on the bottom of the air spring has. I know that with conventional springs when talking about spring rate we talk about deflection with weight, X pounds weight on the spring causes it to compress by Y inches, but how is that going to change? With the suspension on High, it isn't inside the rubber bit so is having no effect but when lower it is encroaching into the chamber full of air. The cross sectional area, and hence pressure, won't change though, just the volume of air needed to fill the available space will be less. So how can that influence the spring rate?

My train of thought, and there is no way I would ever claim to have a full understanding of it, is that the springs are never going to be soft. Irrespective of the height the car is sitting at, the weight on each spring will be the same so it is volume of air in them rather than pressure. Agreed, it needs pressure to lift the car off the bumpstops but surely, once it is at the desired height, the pressure will be the same?

To keep the twin axle trailers I regularly tow level so the loading on each axle is the same, the suspension should be in Standard, but I've found that it feels much more stable if I'm in Motorway. I recently towed a single axle boat trailer with a boat that weighs 1,100 kg so probably around 1,800-1,900 kg total and it was very noticeable that it felt far more stable in Motorway than in Standard. I've no idea why or the mechanics of it, I'm just going on the feeling through the seat of my pants. Maybe it is just that I'm lowering the centre of gravity?