C

chopper007

Active Member
hi all, yep.. i read the posts, and seams to be the driver pack ?
has anyone replaced one.. and then fiddled about with the old one ? replaced anything ? re-soldered ?

mine pops up a fault, and will drive about 200 miles before the dreaded 35mph mode.. i can reset with the unlock software.. and seams to do the same

;-(

i've ordered a whole lot of EAS bits from t-tinternet auction store and intend to replace mine, and then slowly when i get time rebuild and re-furb a whole system with luck..

so if anyone also can recommend the right seals kit / o-rings etc.. would be great !!

ta
 
What seems to be the driver pack? Driver pack has nothing to do with pressure production in any way shape or form.
 
i read a thread that suggested they the 'over pressure' error message could be generated by bad driver pack on the EAS...
have i understood wrong ?
 
chopper007 said:
i read a thread that suggested they the 'over pressure' error message could be generated by bad driver pack on the EAS...
have i understood wrong ?
Click to expand...

The driver pack is a number of switching transistors that power the electromagnetic coils that open or close the various valves. Inlet,exhaust and the four corner valves. To let in or exhaust air from the bags. It does not control the compressor, the diaphragm valve nor the pressure switch. It recieves low voltage signals from the ECU and switches higher voltage that the ECU can't handle to operate the solenoids. Its lifts the solenoids then drops them slowly so as not to damage the seals. It is said the driver pack can cause various fault codes, i don't see how but it is said. It may well be so if something fails and feedback into the ECU takes place. But firstly i would be checking the plugs in the EAS box for good contact then change the pressure switch before i splashed money out on a driver pack. It gets blame for a few things it has no control over.
 
Last edited:
yep agree. Only 3 possible conditions that can be caused by driver pack, and if your EAS works for 200 miles before the error each time, then only last two faults can exist for you.
  1. Internal shorted driver chip or MOSFET could cause one or more valves to be stuck open. EAS would definitely not work properly and you would get fault very quickly.
  2. Bad connector feeding driver pack. Will result in either Inlet, Exhaust or Corner Valves not being opened when requested by ECU. This will cause lack of commanded height changes, and eventually can result in random errors depending on what doesn't move. Clean & Pinch connectors tighter to resolve.
  3. Bad solder joints internal to driver PCB. Will cause similar results to bad connector. Replace driver pack to resolve.

In my case 1st pack had fault 1, and replacement had fault 2.

BUT do the Seal Replacements on Pump & Valve Block, plus check the connector before you replace the driver pack.

Pete
 
chopper007 said:
i read a thread that suggested they the 'over pressure' error message could be generated by bad driver pack on the EAS...
have i understood wrong ?
Click to expand...
The fault "pressure signal constantly high" actually means lack of pressure. Although the driver pack has no direct connection to this, it can cause it. I have a driver pack that does this intermittantly, I have yet to re-test but I found an electrolytic in the pack had failed, as in was getting very hot. Since fitting a replacement driver pack the fault has not recurred proving the fault was caused by the driver pack, I intend putting the repaired driver pack in when I replace the RAD hoses in a week or two.
 
Morning, well I will take a look, will have a replacement driver pack this week which I planned to have a look over connection wise / solder joints etc. then fit and see.
So maybe then I need to look at the pressure switch ? And it a pump refurb ?
 
pwood999 said:
yep agree. Only 3 possible conditions that can be caused by driver pack, and if your EAS works for 200 miles before the error each time, then only last two faults can exist for you.
  1. Internal shorted driver chip or MOSFET could cause one or more valves to be stuck open. EAS would definitely not work properly and you would get fault very quickly.
  2. Bad connector feeding driver pack. Will result in either Inlet, Exhaust or Corner Valves not being opened when requested by ECU. This will cause lack of commanded height changes, and eventually can result in random errors depending on what doesn't move. Clean & Pinch connectors tighter to resolve.
  3. Bad solder joints internal to driver PCB. Will cause similar results to bad connector. Replace driver pack to resolve.
In my case 1st pack had fault 1, and replacement had fault 2.

BUT do the Seal Replacements on Pump & Valve Block, plus check the connector before you replace the driver pack.

Pete
Click to expand...
Sorry but your hypothosis is wrong:)
Not seen one yet with a duff MOSFET or driver chip but could happen, the fault will not be "pressure signal constantly high" though.
Connectors problems will cause random problems but not usually the high pressure signal fault as first evidence of a problem.
Bad solder joints as above.
Electrical noise from the second 2 problems may cause the "pressure signal constantly high" error though but I would expect other faults to show.
 
Datatek said:
Sorry but your hypothosis is wrong:)
Not seen one yet with a duff MOSFET or driver chip but could happen, the fault will not be "pressure signal constantly high" though.
Connectors problems will cause random problems but not usually the high pressure signal fault as first evidence of a problem.
Bad solder joints as above.
Electrical noise from the second 2 problems may cause the "pressure signal constantly high" error though but I would expect other faults to show.
Click to expand...

Maybe the act of unplugging the old driver pack and plugging in the new one clears the fault. :);)
 
wammers said:
Maybe the act of unplugging the old driver pack and plugging in the new one clears the fault. :);)
Click to expand...
No, I have carefully checked the connectors and putting the suspect pack back before I replaced the electrolytic brought the fault back. I ran out of time to test it after the repair as I was off to the UK.
The failed component would have been obvious to a blind man as the potting compound was blackened and cracked.
 
Datatek said:
No, I have carefully checked the connectors and putting the suspect pack back before I replaced the electrolytic brought the fault back. I ran out of time to test it after the repair as I was off to the UK.
The failed component would have been obvious to a blind man as the potting compound was blackened and cracked.
Click to expand...

So how does the driver pack tell the ECU there is an over pressure fault when it is not connected to the pressure sensor. Or is this just a spurious fault? Don't know but would think the triggers from the ECU to the driver pack are diode protected to prevent feedback. So how does it do it?
 
wammers said:
So how does the driver pack tell the ECU there is an over pressure fault when it is not connected to the pressure sensor. Or is this just a spurious fault? Don't know but would think the triggers from the ECU to the driver pack are diode protected to prevent feedback. So how does it do it?
Click to expand...
It's a spurious fault, the lines are diode protected. I'm pretty sure I know how the message is triggered, I'll tell you when I have proved it.:)
 
Datatek said:
It's a spurious fault, the lines are diode protected. I'm pretty sure I know how the message is triggered, I'll tell you when I have proved it.:)
Click to expand...

Certainly an enigma. Because even with the pressure switch the only things the ECU can ever know is low pressure or high pressure. Over pressure is not a function. :)
 
wammers said:
Certainly an enigma. Because even with the pressure switch the only things the ECU can ever know is low pressure or high pressure. Over pressure is not a function. :)
Click to expand...
The only error message I have ever seen is:- "Pressure signal constantly high" which is what I suspect the OP is refering to. As the pressure switch operates in the oposite sense to a normal pressure switch, a logic Hi = low pressure.
Theoretically the driver pack should not be able to cause this fault, but theory and practice are often different when it comes to electronics.
 
Datatek said:
The only error message I have ever seen is:- "Pressure signal constantly high" which is what I suspect the OP is refering to. As the pressure switch operates in the oposite sense to a normal pressure switch, a logic Hi = low pressure.
Theoretically the driver pack should not be able to cause this fault, but theory and practice are often different when it comes to electronics.
Click to expand...

That is the opposite of my understanding. Pressure switch is open circuit low pressure closed circuit high pressure. One day i will test the one i have spare and see if there is indeed just an on or off function or some sort of resistance value in between to inform the ECU of falling or rising pressure.
 
wammers said:
That is the opposite of my understanding. Pressure switch is open circuit low pressure closed circuit high pressure. One day i will test the one i have spare and see if there is indeed just an on or off function or some sort of resistance value in between to inform the ECU of falling or rising pressure.
Click to expand...
Pressure switch is open at low pressure as you say, so you are right, I have muddled my O's & 1's closed = high pressure = logic hi; open = lo pressure = logic ground. It's a simple pressure switch, no analogue funtion.
 
Last edited:
hey guys, sorry, yep the error message was ' constantly high' as you say..
still need to try figure it out.. so will swap out the driver pack, and if not then maybe look for a replacement pressure switch ?
im in no way tech ( or mechanically ) minded tbh, so bow to your expert knowledge..

thanks as ever
 
chopper007 said:
hey guys, sorry, yep the error message was ' constantly high' as you say..
still need to try figure it out.. so will swap out the driver pack, and if not then maybe look for a replacement pressure switch ?
im in no way tech ( or mechanically ) minded tbh, so bow to your expert knowledge..

thanks as ever
Click to expand...
It's very unlikely to be the pressure switch IMO, better to carefully check the connectors if it's not the driver pack.
 
Datatek said:
Pressure switch is open at low pressure as you say, so you are right, I have muddled my O's & 1's closed = high pressure = logic hi; open = lo pressure = logic ground. It's a simple pressure switch, no analogue funtion.
Click to expand...

There has to be something that causes the differential Keith. ;)
 
wammers said:
There has to be something that causes the differential Keith. ;)
Click to expand...
What differential? It's a mechanical switch with built in hysterysis if you mean the difference between the opening and closing pressures.

It's a standard pressure switch except the contacts are reversed from normal. A standard pressure switch with a relay to invert the contact operation works and can be found for less then a tenner.:)
 
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