Another regular on here and LPGForum is a name followed by 3 letters, the first one being upper case, such as CurtisBop that I killed earlier.

Just caught one, CurtisBop posted in Opening Time, I hid the post and banned him only to find that in the meantime, he'd posted the same garbage in Oily bits. So I hid that one too then deleted both. He was shown as online at the time so I wonder what he saw when he tried to post for a third time?

Someone asked recently if there should be a light on the dash to tell you cruise control was operating. The answer was that there isn't and that is confirmed by the owners handbook, but it looks like there might have been one planned at some point.
However, RAVE says:
Cruise Active Indicator
When the Cruise Control System has been activated the indicator will be illuminated. The Cruise System is interfaced to the Instrument Cluster (Z142) via the BeCM (Z238).
(Electricat Troublshooting Manual, Section E2 Warnings and Indicators).

While I had an instrument cluster apart to take pictures for the how to pull it apart thread, I noticed that the spaces for the warning lights are actually labelled on the main pcb. Interestingly, the labels don't match up with the handbook or the actual cluster displays.

Looking at that (which is the rear of the RHS of the cluster) along the top we have, from right to left (which would be left to right as you look at the dash), Suspension (correct, the picture of the car with an Up arrow), Service E (obviously where the service engine soon light lives on those versions, or markets, that have it), Check E (check engine, so also correct) and Brk Pad (presumably for a brake pad wear indicator which we don't appear to have, the owners handbook doesn't mention and the overlay has no image, just plain black). Then if we look at the lower row, also going from right to left, we have a space where there is no bulb, then Trail (which is the trailer indicator repeater to tell you your trailer indicators are working), Spare (which is pretty self explanatory) and Cruise A (which I assume to be short for Cruise Active) yet that bulb is the one that lights up showing the gear symbol when you change range from High to Low and vice versa. So someone, at some point realised that they didn't have enough spaces for bulbs as they did warnings they wanted to show. That doesn't explain why they didn't decide to use the one marked Spare for the ratio change light or even the cruise active light......

I noticed something else I can't explain, on the front of the pcb, in the position where there isn't a bulbholder (far right, second row in the above pic) there's what looks to be a daylight sensor.

There is a matching clear section in the cover that goes over it so it must be there for something but what? Is there anything on the P38 that alters depending on whether it is daylight or dark? Nothing that I can think of but maybe someone else has an idea of what it might be there for. It isn't for the dash illumination as that can be set at different levels depending on whether the lights are on or not, so what does it do?

A dob of grinding paste on the screwdriver tip helps as it stops it from riding out and chewing up the head.

Plastics? But they will be off when you've taken the seat out. There's a flat of material between the backrest and base that is clipped on, if you lever that long plastic clip then you can separate the two halves. There's no need to take the backrest off though.

Nothing like as much here, probably 3 or 4 a week compared with that number per day, at least, on LPGForum. If I'm about I have both open on tabs and just refresh every so often so any that does appear gets dealt with within an hour so so. Brian obviously gets up earlier in the morning than me as I regularly find 3 or 4 on LPGForum that he's already dealt with when I check first thing.

OK, so I threatened to do it and Tom talked me into it, so here goes:
Pulling an instrument cluster apart.
Primarily on how to swap one of the gauges (in Tom’s case, the fuel gauge) but would apply to any of the internals really. If you don’t know how to get the instrument cluster out, drop the knee panel, undo the 4 screws (two at the top, two at the bottom obscured by the knee panel) that hold the instrument panel surround and as you lift it out, unplug the connector to the fuel flap release. There’s 2 connectors to the bottom of the instrument cluster. With ignition off and the key safely inside the house, unplug these two connectors. There’s a screw in each corner that secures the instrument cluster but they don’t have to be fully removed, just unscrew them until the instrument cluster is free. Once all 4 are free, lift the cluster out.

To take it apart, completely remove the 4 screws (as they also hold the front and back together), unplug the connector to the speaker marked 1 (which is what gives you the annoying beeps as well as the tick, tick from the indicators) and using a fingernail, unclip the translucent back cover at the points marked 2 along with one on each side.

Hinge it upwards (there’s another fixing in the centre that will pop out) and it will come off (and tear the security seals along the top) and expose the main pcb with the ribbon cable going to the display. So you’ll see this:

Notice the 4 groups of 3 screws (circled in red), these are what hold each of the individual gauges in place and also provide their electrical connections. Loosely sit it on the translucent cover and turn it over. On the top you’ll see two black lugs which will pop open if you press in with your thumb and push it out and you can hinge the whole front out.

The front is in three parts, the clear outer, the black surround and a plate that goes around each gauge. With that off you are left with the white plastic body with everything attached. If you want to change one of the gauges you just undo the 3 screws that hold it to the pcb and out it comes.

The mileage information is held in one on the chips on the main pcb, so as long as you retain that, everything else can be changed. I know there’s at least 3 different style of gauges, some have graduations every 2 miles on the speedo, some every 5 miles and then there’s the ones fitted to later cars with a dark green background rather than black as on the earlier ones. There would be nothing to stop anyone swapping all the gauges and the message centre display as long as you keep the original main pcb. If you were to swap the main pcb and it has a lower mileage than is stored in the BeCM, then the mileages can be synced but be aware it will always take the higher one of the two. So if you’ve got a low mileage car and you get a spare panel from a higher mileage car and swap the pcb, your mileage will suddenly shoot up. Incidentally, the BeCM only stores to the nearest 100 miles too, so if your BeCM says you’ve done 125,800 and your dash says 125, 870 and you sync to a lower mileage pcb, you’ll lose 70 miles (so don’t do it just after the MoT).

Putting it all back together is just the reverse of taking it apart but be aware when refitting it that there are lugs that fit into holes next to the screws that hold the cluster in place so you need to wiggle it about a bit to make sure they slot in place. Don’t forget to plug the speaker back in either. Don’t turn the ignition on with the instrument cluster out or unplugged (hence the warning about leaving the key in the house) or you’ll be dealing with SRS, and possibly dashboard, faults.

Calibrating the gauges.
While you’ve got it out, you may as well calibrate the gauges if you are really sad. The BeCM sends a digital signal to the cluster which uses digital to analogue converters to drive the gauges. As they are electromechanical, there can be differences from one to another so if you were to swap a gauge you might find it will read slightly differently to the old one. With the instrument cluster out, break the yellow paper seals so you can remove the translucent plastic cover (which will also mean unplugging the speaker) and if you look along the top of the circuit board you'll see a row of three blue trimmer pots on each side. These are used to calibrate the gauges.

On every P38 I have driven except my ex-plod with a calibrated speedo, they all read over so an indicated 70mph is usually a true 65-67 mph (for type approval purposes and speedo can legally over read by up to 10% but cannot under read at all). To calibrate the speedo you first need to know how far out it is, by how much and in what way by comparing the speedo reading against a sat nav. Remember that the GPS on the sat nav will only be 100% accurate when travelling at a constant speed on a flat, straight piece of road.
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If you have a GEMS and a Nanocom (it may be the same on a Thor but I don’t have one to try it on) that makes it very easy as in the ABS menu there is a setting (ABS- Diagnostic-Utilities-Speedo) that causes the speedo to read around 50 mph (Nanocom documentation says it will make the speedo read 100 mph but on all that I've tried it on it reads about 50 mph). So you can set that, make a mental note of what it reads, then drive holding your speed at that same point and compare your actual speed on the GPS compared with what the speedo says. Then drive at different speeds and check them against the GPS so you have an idea of how far out it is at different speeds. You’ll now have your baseline figures so can adjust from there. The trimmers you need are marked VR3 and VR4.

VR4 deals with Offset and adjusts the reading by the same amount over the full range. So if it permanently reads 5mph over, then you adjust that with VR4. It is pretty rare for the offset to need to be adjusted. VR3 deals with slope so if it reads OK at 20 mph but the error gets progressively greater the faster you go, adjust the slope until it is correct over the full range. With the instrument cluster surround out, the cluster itself in place but not screwed in and the translucent cover partly loose, you can get in there with a very short trimming tool (I used the screwdriver bit from a set of the interchangeable bits) but be careful as you only need to give the pots a tiny bit of movement (many years of tuning radio transmitters for maximum power means I've got pretty good at it). On a GEMS, once you’ve seen where the needle sits when driven by the Nano all you need do is use it to drive the speedo to the figure and adjust VR3 so the needle is reading what your actual speed was at that reading.

If you feel like having a play while you are in there, VR1 deals with the Temp gauge reading, VR2 the fuel gauge reading while VR5 and 6 do the same as 3 and 4 but on the rev counter (can't remember which is which though but you have the same offset and slope adjustments on those two). Bear in mind that the fuel and temp gauges are fairly heavily damped so won’t respond immediately to any adjustments.

and it's a digit short of a full set https://www.ukphoneinfo.com/0321-numbers

Testing open circuit means that there's a break. Usually if that's what you get when testing the base, it's a break, or more likely breaks, in the element. If you get that when testing the backrest, it's usually a break where the wiring connects to the element.

Soldering iron, solder, bit of flexible wire and heatshrink tubing.

You've got to take the seat out first......

Seat needs to come out, reclined fully so it lays flat and you should be able to see where the break is on one side without separating the two parts.

No idea what could go wrong but if legit a link might be a good idea. Tried Google but all I got was print companies in Devon......

They can be seen if you recline the seat fully so it is almost flat.

Yes. The two elements are in series so if one is open circuit that seat won't work. If it is the backrest that is open circuit that is usually the easy fix, the wires break where the normal wire joins the end of the element at the base of the backrest. You'll need to take the seat out to solder it though.

I did mine 10 years ago when I first got the car, still no leaks.....

Pierre3 wrote:

IYou can be failed for orange bulbs not being orange enough, slight misalignment of headlights, incorrect design of number plates

All of those would be a fail here too. Indicators must be amber so when the orange paint starts to peel off and they show as white, that may be a fail or it may be an advisory depending on the mood of the tester and how white it is. Number plates too must be the correct font and spacing so ANPR cameras can read them (the argument they use is that if your car was stolen and had dodgy plates they wouldn't be able to track where it was if the ANPR systems couldn't read it, nothing to do with not being able to read it when you get flashed by a speed camera at all). They aren't too bothered about lights as long as there is no light showing above the horizontal line when on dip. The ones that fail regularly on lights are those where the plastic goes misty (some Renaults, Nissans, Hondas, Mercedes, Toyota, etc) so the light just gets scattered and there isn't really a beam there at all.

When the foglights can be used can be set in the BeCM, there's multiple different options so they can be switched on with just sidelights or with dipped beam or only when the rear fogs are on and so on. I think it used to be a case that front foglights could be used with sidelights and dipped beam but went out when you selected main beam. The theory being that if the fog was light enough that you could use main beam without the reflected glare dazzling you, then you didn't need foglights on. Mine is set in the BeCM for sidelights and dipped beam so may well go out if I use main beam, I've never looked to see. The problem I see with the DLRs on some cars is that they are much like a bright sidelight, so no beam setting at all, just a bright blob of light. I've taken cars with modern type lights in for MoT and the cut off is very sharp and is done on the back of the lens rather than an old school reflector and relying on the form of the outer lens. Always amuses me when sitting in the queue to get on the ferry and you'll see people trying to work out where to stick the beam benders on their plain plastic light covers.

Much, much better. When it is taken for test it is tested on the fuel it is presented for test on (although you'll probably have to tell the tester or he'll just test it assuming it is on petrol). Limits on LPG are CO 3.5%, HC 1200pmm, on petrol they are CO 0.2%, HC 200ppm and lambda between 0.97 and 1.03. Lambda isn't checked on LPG.

In saying that, it still won't be running perfectly on LPG if the petrol system is out (by how far? What actual readings did it show?), so might be worth checking it over anyway. High CO meas it is running rich so could point towards a dodgy lambda sensor while high HC is unburnt hydrocarbons so excess means incomplete combustion so points towards plugs and/or HT leads.

That's always the way, you start on one job then notice something else that needs doing while you are in there. In most cases it hasn't yet made it's presence felt yet but will do sooner or later. While changing my intermediate steering shaft recently I noticed one of the engine mount rubbers had perished and split so I've got a pair of those to fit sooner or later. I've got the new ones and it isn't a big job but it does involve dragging the engine crane out to support the engine to change them and that's down the side of the garage buried under all sorts of other rubbish.