[markostam]

Hey folks been lurking for a while first time posting! I recently picked up the oxford green msport off of BAT and am really excited to start digging and restoring it.

Overall it seems in good mechanical shape with a few random niggles that are throwing me for a loop (first e34, I’m an e30 guy up till now) that I thought I might bounce off the community.

1. There’s a disconnected two prong plug on the right side of the engine (see pics)... any idea what that is to???
2. EDC is still present and not leaking as far as I can tell but the EDC button only lights up on P, not on S (see vid
   ). The suspension seems extremely firm and I cant tell a difference when I press the switch which from my reading means it may be stuck in S. No EDC codes of any kind of the dash... I’m thinking about starting with replacing the accumulators and getting the codes read on the EDC with an INPA or Autologic or similar? Any other thoughts??

Thanks in advance!!

 

[markostam]

The plot thickens: got a quick Autologic test at German Performance Service today. Rob was super cool about talking through everything and didn't charge for the service which was awesome.

Turns out there were two EDC codes stored: 0001 Steering Angle Signal and 0006 Valve solenoids. He said the computer could register the switch changing from P to S but it doesn't seem to affect the function of the shocks. He cleared them all out but it didn't seem to affect the EDC function.

The thing that worries me is the Valve Solenoids error which seems like it may be an issue on the actual shock which means maybe they have a visit to Poland in their future... Any thoughts troubleshooting on this at least to narrow down to a specific shock? I am pretty committed to trying to keep EDC at this point since I feel like it's a big part of what makes this car special.

 

[mottati]

id agree it sounds like the solenoid in the shocks, but i'd also check the wiring too, just in case there's a break/short. Especially at the rear. Autologic should be able to manually switch the solenoids, and you can hear them click when they work. Maybe see if they can narrow that down.

The wiring connector, do you have the intensive washers and headlamp washers?

 

[markostam]

No headlamp washers, not sure about intensive. It’s been suggested that this may be a secondary air pump plug (emissions gizmo) that was only implemented on the 530 but not the 540. Several other 540 owners also have the unterminated plug in their engine bays so it’s not EDC related as I had first thought.

Yea doesn’t sound great on the shocks... Current plan is to

1) replace accumulators (cheap and they likely need it anyway)
2) try replacing the switch (can always return to FCP if it doesn't help)
3) check the wiring harness.

If none of those helps, I’ll take it back to the shop to have them do a bit more detective work with the Autologic likely followed by sending a pair out to Nagenast.

Will try to keep a thread of any troubleshooting progress.

 

[markostam]

So I removed the EDC switch to try and open it up to see if the bulb was just faulty on S. Couldn’t get it open it’s pretty tight... BUT I didn’t get any new errors with the switch removed.

I would expect to get an “EDC inactive” type error with the switch gone if the switch/EDC comp was functioning correctly no?

 

[M5touring reg]

The EDC III system works as it should (if it does) without
the switch. All the P/S switch does, is to give the driver
the alternative to lock the EDC system into the S mode.
All E34 M5 3.8 cars have the adaptive suspension set up.
-
courtesy of mregistry:
-A control switch for the Adaptive M Suspension, allowing the EDC shocks to be locked in to their firmest position.
unquote

 

[markostam]

@M5touring reg you’re saying that the computer will not complain and system will function normally without any switch present?

This is surprising given members seem to have solved the limp mode hard shocks issue just by replacing the switch for example here EDC always firm, regardless of switch indicating the performance of the system is in fact tied to the switch.

 

[markostam]

Anyway, did the accumulators today. Picked up a new set of Febi made in germany ones from Bimmerworld. The ones on there ones were 16 years and 50k miles old and had blown nitro bladders.

I got a good look at the rear EDC shocks while I was in there. Overall look quite solid with no wetness or drips near the solenoids. One thing that did worry me was a funky seal on the drivers side shock. Could this be the solenoid error root?

Not a hard job but not super pleasant due to tight clearances and pentosin drips. Haven’t put a lot of miles on it but not seeing much of a difference in feel of the car. On to the next checklist item I suppose.

 

[M5touring reg]

@M5touring reg you’re saying that
the computer will not complain and system will
function normally without any switch present?
This is surprising........

-
@markostam -
.......how come this is surprising to you ?
As said, ALL 3.8 Li E34 M5/M5touring have the adaptive suspension set up, EDC III, i.e. the system works
(if it does) in the P-mode and without the switch.
The switch is normally a part of the ,Nürburgring package’-(extra pay)- option only, but can easily by added (which many have done) as all the connections are already in place. Cars w/o the factory Nürburgring package option have no switch.
The EDC suspension system works without it. However once there is indeed a fault in the EDC system it
can be tricky to find what the problem is as the OBC-system
will not show an error code unless the system fails all together,
like with the most common failure, a cable break between the control unit and the rear of the car.
You should consider to let someone with an
error-code-diagnos reader to do an error code check.

Thank you, for your detailed write up and the informative
pictures !!!!