EAS height settings

**PaulP38a** · 26th April 2009, 12:04 AM

Decided to try to adjust my inconsistent ride heights today. Not a lot of luck really...

Home-made EAS diagnostics cable - all continuity tested ok for correct pin-outs. Current EASunlock software and previous 2 versions just in case. HP laptop/tablet-PC with USB to serial adaptor (PL2303 chipset I think).

Seems Windows 7 Beta doesn't know about USB-Serial adaptors. Lucky I kept Vista on another boot partition.

Plugged in to OBDII port under the dash, fired up the software, selected correct serial port, initialised and got the familiar beep on the dash that indicates the EAS is talking to an "outsider". However, instead of getting the FF receive codes, I'm getting PP codes. Can still raise/lower the car, start/stop the pump etc via software but can't read heights - only getting 0 values.

Did a quick Google search for similar problems, and found someone who solved the problem by swapping laptops. So I plugged it in to the garage PC instead, still via USB and extender as I didn't have a serial cable long enough to reach the car. Same problem getting PP receive codes and no height info. Has anyone experienced this and if so, what was your fix please?

What I was trying to correct was a variation in corner heights as shown below, and considering that my car has a 50mm lift so it should be higher than a standard P38A anyway.

Setting __FL__FR__RL__RR
High______935_920_940_930 (mm from ground to under wheel arch)
Standard__880_880_890_890
Highway___855_850_870_870
Access____835_835_850_855

So... I've got 100mm travel between Access and High at FL but only 75mm at RR. However RL on Access still sits approx 5mm off the bump stop ?

Other than the 25mm overall variation between FL and RR, does this range look about right?

If there is only 20mm between Highway mode height and the bump stops, this might explain why the ride is so hard and bumpy at times. Even 45mm from Standard height to the bump stops seems a bit short. I'm pretty sure my car has extended bump stops due to the HRA lift kit. Can anyone see any problems returning to standard size bump stops to increase downward travel?

I'll measure my bump stops tomorrow. Can anyone tell me what "standard" bump stop lengths are please?

I'm going to go Google some more now...

cheers
Paul.

**Remy** · 26th April 2009, 11:28 PM

EAS Settings
Hi Paul,
see P38A Suspension - LandyWiki

Height Measurements

The calibration procedure for P38A requires blocks to sit under the bump stops to measure heights. the vehicle needs to be on a level surface. The height should be as follows:
Mode Height Offset from Standard
Access 730mm +- 7mm -60mm
Low Profile 770mm +- 7mm -20mm
Standard 790mm +- 7mm 0
High Profile 830mm +- 7mm +40mm
Extended Profile 850mm -7mm/+17mm +60-70mm

These heights are for P38A and measured to the center of the wheelarch with new tyres. The factory fit Pirelli Scorpion has 11mm of tread when new. You will need to make adjustments for rims and tyres on yours

Cheers,
Remy

**PaulP38a** · 26th April 2009, 11:52 PM

Many thanks Remy - looks like a useful site too.

Interesting... seems mine is sitting 100mm higher than stock on Access mode. Also looks like there should be a 40mm diff between Highway and Access mode instead of the 20mm I've got.

I'm getting the impression that my extended bump stops are the problem with not enough downward travel but will need to check travel on the shocks too.

I've seen these blocks mentioned before and wonder what they're used for. Surely, a tape measure is the most accurate method of measuring height without any blocks in the way?

Here's the method I use:
I jump in the car, close the door, select the height and let it adjust. Then jump out, leaving the door open to stop it settling and measure the heights with a tape measure.

I did my measurements with near new Coopers running approx 32-34psi all round.

Cheers, Paul.

**andrew e** · 27th April 2009, 11:58 PM

you will be getting a little present in the mail in the next day or 2 paul.

Andy

**PaulP38a** · 28th April 2009, 12:09 AM

Originally Posted by andrew e

you will be getting a little present in the mail in the next day or 2 paul.

Andy

I like presents... thanks Andy. Hopefully I'll have the Rangie back from CMW before the weekend so I can try them out.

Cheers, Paul.

**tasi devil** · 28th April 2009, 07:24 AM

Paul i am following this and i'll be interested to know how you go , we're doing mine as soon as we get a reply back from Faultmate.
have saved for my mechanic mate all appropriate links , so it'll be interesting how it goes. we've got a diagram for the blocks to make up, but i think we just need to extend them for the Arnotts GIII's ?
does yours have Gen III Arnotts air springs ?

............tasi

**PaulP38a** · 28th April 2009, 02:54 PM

Originally Posted by tasi devil

does yours have Gen III Arnotts air springs ?

yep, I have the Arnott Gen III's too. I still don't understand what the blocks are used for though.

Cheers, paul.

**BigJon** · 28th April 2009, 04:57 PM

Originally Posted by PaulP38a

. I still don't understand what the blocks are used for though.

Cheers, paul.

They give the system a fixed reference point for suspension heights. This enables you to calibrate the system.

**p38arover** · 29th April 2009, 12:18 PM

Measuring from the ground to the wheels arch is not the ideal method.

Measure from the centre of the wheel to the wheel arch. This overcomes differences in tyres pressures, differences in tyre size, etc.

I've just measured mine:

Setting __FL__FR__RL__RR
High______530_520_515_520 (mm from wheel centre to under wheel arch)
Standard__490_480_450_460
Access____430_425_400_415

I might need to get the calibration blocks out and do a cal. It's not been done since I've owned it.

**Hoges** · 4th May 2009, 10:24 PM

Sorry for this long response but it sort of summarises my "research" on this issue thus far...

There are some critical issues to be kept in mind when wanting to do a proper EAS calibration on a P38:

1. The official calibration blocks are specifically designed for use with a Test Book. Their overall “length” dimensions do not tally with the so-called “standard” floor-wheel arch specs e.g. 790mm standard / 730mm Access / 830 mm high etc when using the Faultmate or DIY cable with the excellent Sourceforge s/w from Rishi and Storey Wilson.

2. The so-called “standard” settings presume that all body panels are accurately fitted, that the chassis is “straight”, that the body sits squarely on the chassis and that the mounting points / bushes are all equally compressed, and that the overall diameter of the tyres equates to the OEM Pirelli Scorpions with 11mm of tread….

3. Land Rover’s EAS Systems Information Document (1998) (EAS SID) clearly states that the critical measurement for standard height for a P38 is the distance between the bump stop studs and the axle plates NOT the floor to wheel arch heights…these latter dimensions being ready approximations IF all the issues in Para 2 are complied with… the 790mm etc distances would appear to relate to the RR “Classic” (pre 1995).

4. SO: to get an accurate measurement for a P38: the EAS SID states that standard height occurs when the bump stop stud to axle plate distances are 100mm +/- 4mm for the front and 105 +/- 4mm for the rear.

5. While the EAS SID does not say so explicitly, one then presumes that we add 40mm all around for “high”, subtract 25-30mm all around for highway mode and 60mm all around for Access, and set the EAS bit counts to achieve this accordingly.

6. Using bumpstop stud -axle plate distances gets rid of any ambiguity and other errors re. tyre diameter/tread depth considerations.

7. IF for convenience one now wishes to continue using floor-wheel arch measurements, these individual measurements need to be taken and recorded when the bumpstop stud-axle plate distances are set as in Para 4 so as to be able to account for any build differences outlined in Para 2.

8. I recently undertook an experiment using a home made set of standard blocks…100mm front, 105mm rear. I removed the bumpstop cushions and “sat” the vehicle on the blocks then measured the floor to wheel arch distances (standard 255/65/16 Cooper H/T 9mm tread).

The wheel arch -floor level was about 810mm… +/- 7mm all around the 4 corners…. not the 790 mm or thereabouts expected...

I have yet to complete my experiments in search of the “correct” heights

Will keep you informed

cheers

Hoges

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