P38A A series of faults

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Grrrrrr said:
If it worked before and has stopped then it has to be a connector sonewhere. The OBD plug sometimes corrodes from water ingress. And then there's the infamous connectors behind the passenger kick panel / A-post.
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This is why I went in with the contact cleaner on the OBD socket, I couldn't see any evidence of corrosion however using the contact cleaner combined with plugging in and out the plug should have helped clean the contacts. I need to repeat elsewhere...Will look up the thread highlighting where all the connectors are located.

Mark Piercy said:
Take the muffler off the valve block, close the doors and listen to its behavior.
If it's pumping, stopping and adjusting on level ground there's a conflict with height sensors.
Live data will show if the figures are flickering or there's a difference in the height sensors.. :)
Click to expand...

A conflict with the height sensors would make sense, the last time that I could see live data (I can't see it currently due to being unable to get EAS Unlock to talk to the car) the figures were flickering.

Another thought was; what would poorly sealing NRVs look like? They were theory parts that I could refresh in the Valve Block rebuild and didn't look in the first flush of youth
 
Slooby said:
Well I am utterly befuddled; got my EAS cable and FTDI USB to Serial adapter out of the packet they were sent back to me in, having been back to the chap who made the EAS cable to confirm that they were ok, which they were, then went through the sequence of getting the laptop running, cable plugged into the USB port and communicating, then car ignition on, cable plugged into OBD port, EAS unlock launched, set to communication through Comm Port 5 (which is where device manager said it was) clicked 'Initialise' and watched as the TX buffer reported the repeating FF and 01 codes as expected, but the HX buffer just said: PP

Trying each of the three USB ports on my Laptop made no difference, then removing the OBD socket from the plastic trim, spray in contact cleaner and with the aid the the EAS cable help it do its thing. No difference.

After being round the houses for a while I just thought sod it; see if the suspension will work with the engine running...it works fine...well ish...the pump keeps cycling on and off jiggling around with the front suspension. No sign of any leaks as the suspension hadn't sunk since Sunday when I left it. Also tried leaving the door open for it to fill the tank and it stopped running after less than a minute.

So, there's clearly something odd going on; still not sure if the pump running every few minutes is an indication of a problem about to manefest itself in an imminently burnt out pump or if being driven will keep it in check, then there is the question as to why I cannot communicate with the EAS controller, clearly something sitting between the OBD port and the BECM/EAS ECUs has gone walkabout, but where?
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You have to install the correct driver BEFORE you plug in the FTDI USB to serial adaptor or the EAS suite will not function as there will be no RTS signal. What you have now is a generic Windows driver that don not use RTS/CTS, this will have to be removed and the correct driver installed.
 
Device Manager says I am using an FTDI driver though, or at least that's what I think it is telling me, unless the Microsoft generic would identify the adapter as FTDI itself?
 
Putting my troubles with EAS Unlock to oneside for a minute; if the height sensors are in conflict can they be reset or is that one or more is starting to fail and in need of replacement? Just trying to plan ahead for taking the car for an MoT tomorrow and whether I am going to need to perform more surgery
 
Slooby said:
Putting my troubles with EAS Unlock to oneside for a minute; if the height sensors are in conflict can they be reset or is that one or more is starting to fail and in need of replacement? Just trying to plan ahead for taking the car for an MoT tomorrow and whether I am going to need to perform more surgery
Click to expand...
Height sensors in conflict? Not sure what you mean by that. The height sensor is just a variable resistance.
 
Slooby said:
Putting my troubles with EAS Unlock to oneside for a minute; if the height sensors are in conflict can they be reset or is that one or more is starting to fail and in need of replacement? Just trying to plan ahead for taking the car for an MoT tomorrow and whether I am going to need to perform more surgery
Click to expand...

The track can wear and have blank spots or dirt buildup. You might get away with adding or removing some bit counts all round. The default bot counts for each height are posted somewhere and you need to make sure you're not near a cross-over or that can cause odd behaviour.
 
Datatek said:
Height sensors in conflict? Not sure what you mean by that. The height sensor is just a variable resistance.
Click to expand...

Just using Mark's terminology from earlier; was wondering if the EAS ECU was getting conflicting information from all the sensors, or an erratic signal from one and therefore trying to compensate.

Grrrrrr said:
The track can wear and have blank spots or dirt buildup. You might get away with adding or removing some bit counts all round. The default bot counts for each height are posted somewhere and you need to make sure you're not near a cross-over or that can cause odd behaviour.
Click to expand...

I did read that is possible to switch height sensors from side to side in an effort to get them to use a different part of the resistor track. When you say 'cross over' do you mean in the bit counts based on the resistance value from the sensor due to it being in a 'dead zone' due to the wear?

Just going to try uninstalling the FTDI driver and re-installing now
 
Genuine FTDI Driver (version 2.12.36.4 previously and again now after complete re-install) uninstalled and re-installed, made no difference, EAS Unlock TX buffer doing the repeating FF/01 Hex code, HX just has the single line 'PP'

Seeing as the USB ports on my laptop all work fine, and the cables apparently were all fine according to the seller, the problem has to be in the car.
 
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Slooby said:
Just using Mark's terminology from earlier; was wondering if the EAS ECU was getting conflicting information from all the sensors, or an erratic signal from one and therefore trying to compensate.



I did read that is possible to switch height sensors from side to side in an effort to get them to use a different part of the resistor track. When you say 'cross over' do you mean in the bit counts based on the resistance value from the sensor due to it being in a 'dead zone' due to the wear?

Just going to try uninstalling the FTDI driver and re-installing now
Click to expand...

I cannot remember if it is the early or late models that can be swapped but Data or Tomcat would.

Each height has a default range. If it crosses from e.g. normal to high as the suspension bounces along it may not know if it is in high or normal and throw a fault. If it hits a blank spot on the track it will have no voltage and no idea what the height is on that sensor. Swapping across the axle might pinpoint that vut you can only do it with certain years.
 
Grrrrrr said:
Each height has a default range. If it crosses from e.g. normal to high as the suspension bounces along it may not know if it is in high or normal and throw a fault. If it hits a blank spot on the track it will have no voltage and no idea what the height is on that sensor.
Click to expand...

There's the rub though, the pump is kicking in every minute or so and the front suspension then rises and lowers an inch with the car sitting at idle, not moving, just sitting on a yard made of road planings (so a smidge uneven but not more than an inch difference). No errors on the dash, just a rather busy EAS for a stationary vehicle if you ask me.

As I want to get on and use the RR next week to move a few things about with my trailer and cover a fair bit of distance in the process (Tonbridge to Basingstoke and then Basingtoke to Chesterfield and back via Cambridge) I don't want it to let me down just as I role up onto the M25 for the first time! With no prior experience of the P38 EAS I'm uncertain what to expect from it, but to me sucha busy system at idle doesn't seem normal
 
Slooby said:
There's the rub though, the pump is kicking in every minute or so and the front suspension then rises and lowers an inch with the car sitting at idle, not moving, just sitting on a yard made of road planings (so a smidge uneven but not more than an inch difference). No errors on the dash, just a rather busy EAS for a stationary vehicle if you ask me.

As I want to get on and use the RR next week to move a few things about with my trailer and cover a fair bit of distance in the process (Tonbridge to Basingstoke and then Basingtoke to Chesterfield and back via Cambridge) I don't want it to let me down just as I role up onto the M25 for the first time! With no prior experience of the P38 EAS I'm uncertain what to expect from it, but to me sucha busy system at idle doesn't seem normal
Click to expand...
It certainly shouldn't be busy at idle as you describe. If the bit count across the front axle is different by more than 5, it can cause the front to dance.
As for the EAS, if the driver is correct, it comes down to a connection problem either your EAS cable, the OBD connector, the EAS relay or the connector to the ECU. It could also be the ECU although failure is rare.
 
With no way to interorgate my EAS ECU I can't check to see what's going on with the sensors

I have to take it on trust that my cable checked out ok having sent it back to the seller for testing and him reporting back that it checked out ok, he even sent me a new FTDI adapter just in case, even though he couldn't find anything wrong with the one that I sent back.

With the exception of the busy front end when the engine is running the EAS system appears to be working normally, it will raise and lower on comand from the height control button, the EAS lock button appears to work, there are no warning messages, turning the ignition off/shutting the driver's door results in the usual sound of solenoids shuttling, it's even sitting at a sensible height for once, so superficially it all seems to be working. This leads me to think that the issue must be relating to the OBD connector and how it communicates with the EAS system. If anything else in the system were faulty then surely I would be experiencing much more wierdness and warning lights?


I'm either going to just have to risk it or abandon my plans to use the P38 and go hire something Japanese again
 
Slooby said:
With no way to interorgate my EAS ECU I can't check to see what's going on with the sensors

I have to take it on trust that my cable checked out ok having sent it back to the seller for testing and him reporting back that it checked out ok, he even sent me a new FTDI adapter just in case, even though he couldn't find anything wrong with the one that I sent back.

With the exception of the busy front end when the engine is running the EAS system appears to be working normally, it will raise and lower on comand from the height control button, the EAS lock button appears to work, there are no warning messages, turning the ignition off/shutting the driver's door results in the usual sound of solenoids shuttling, it's even sitting at a sensible height for once, so superficially it all seems to be working. This leads me to think that the issue must be relating to the OBD connector and how it communicates with the EAS system. If anything else in the system were faulty then surely I would be experiencing much more wierdness and warning lights?


I'm either going to just have to risk it or abandon my plans to use the P38 and go hire something Japanese again
Click to expand...
It does sound like it's just a comms problem. As I said the dancing front end may just be the bit count difference across the front axle.
You could get a set of Schrader valves and a 12 volt tyre compressor as a manual inflation back up
 
Well that was a complete waste of a morning.

Suspension went nuts just as I set off for the MoT and went up to full ride height then refused to budge, button pushes just getting flashing lights and then it giving up, air compressor running every 30 seconds or so, turning it off an on again nothing made a blind bit of difference. Decided to go anyway. Filled the fuel tank (90 litres) which cost a frigging fortune. Something is banging away merrily on the neraside rear on every bump, can't see anything loose or perished in the bush department.

Arrived at the MoT (Kwik Fit Tonbridge) station late and missed my slot, with no more till Monday, utterly f:mad::mad::mad:ed off came back and then as I rolled back into the village the suspension 'fixed' itself. Driven it round the back into the orchard to be abandoned with my other projects once again what an utter POS :mad:
 
Grrrrrr said:
I cannot remember if it is the early or late models that can be swapped but Data or Tomcat would.

Each height has a default range. If it crosses from e.g. normal to high as the suspension bounces along it may not know if it is in high or normal and throw a fault. If it hits a blank spot on the track it will have no voltage and no idea what the height is on that sensor. Swapping across the axle might pinpoint that vut you can only do it with certain years.
Click to expand...
Later models can be swapped but not early ones
 
Datatek said:
It certainly shouldn't be busy at idle as you describe. If the bit count across the front axle is different by more than 5, it can cause the front to dance.
As for the EAS, if the driver is correct, it comes down to a connection problem either your EAS cable, the OBD connector, the EAS relay or the connector to the ECU. It could also be the ECU although failure is rare.
Click to expand...
I would try another laptop.
 
nigelbb said:
I would try another laptop.
Click to expand...

It's the only working one that I have and all three USB ports work fine for other duties.

Currently sitting in the RR having shunted my trailer out into the Orchard to unload it. Suspension is all over the shop and now when tge compressor kicks in the engine struggles to idle due to the additional electrical load... Could this be signs of a faulty alternator and therefore insufficient ergs are available to run everything causing the car to do random things?
 
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