RM1 Module Schematics ?

[sofiabghome]

Gents,

Okay, here is what happen with my 840ci '97. Had the battery off and have not driven the car
for over 6 months.Put the battery back in and fired up with a blink of an eye.

That day was raining, and when I started the engine my finger was on the wiper blade to swipe
ones position (down) but the wipers did not move as this is normal. Has been allwas like that when
you start the engine and it takes somewhere around 3-4 seconds till the wiper start to operate.
Sort of while you are cranking all of the accessories are disabled in order all of the power to go to
the started.

Again, I was inpatient while the engine was starting and my hand was on the single wipe option
(down) which should not be a problem at all but apparently the RM1 did not like that...

Right after power reached to the RM1 module the wiper blade did swipe ones BUT the home position
is no longer were it suppose to stay, rather sits at 45 degrees across the windshield. I did the procedure
of trying to re-learn by the BMW AG instructions but never helped.

Another issue come along with this is ones you start the engine and drive out all windows including the
sunroof opens all the way, imagine its like when you unlock the door and you hold the key on the "left
position" all the windows and sunroof open all the way, that is what it does now on its own lol

Never seen or heared of this issue in the E31 community, I am sure I am the only one

I have the RM1 module apart and if anybody is willing to share mode data or share the schematics if
there any to the RM1 will be very helpful.

Thanks,
Anri

[revtor]

What makes you so certain the problem is with the A5 relay module (RM) and not the A1 general module (GM)? I'm not saying it isn't, just wondering... The wiper relays are driven via the RM but controlled by the GM.

I don't think anyone ever made schematics of the RM or GM. Isolating problems between GM and RM can be difficult as both communicate over an undocumented interface. However the GM has a history of weird behavior due to aging electrolytic capacitors while most RM failures are down to corrosion damage due to water ingress. Of course there's a first for everything and the symptoms you describe are different from the usual GM issues.

The wipers not stopping in the park position could be a mechanical issue. To park the wipers the GM runs the wiper motor in reverse for a brief moment. There's a mechanism on the wiper motor that will pull the wipers to the parking position when running in reverse. There have been reports of this mechanism seizing up and then there's no difference between the motor running forward or in reverse. The result is exactly as you describe: The wipers park halfway the windscreen.

Another potential cause could be a blown fuse F15 (typically due to a broken washer pump). When this happens the wiper reset contact no longer gets power and the GM does not know where the wipers are on the windscreen. The behavior is different from the situation above, though. The wipers will run for exactly 16 seconds and then park randomly on the windscreen. If yours can still do exactly one cycle but park wrong, it is not fuse F15.

The windows/sunroof issue is bizarre. I have no explanation for it, but the interesting bit here is that the sunroof motor is not driven via the RM but via the A33 sunroof module which on its turn is controlled by the GM. The RM provides power (and current monitoring) for the sunroof motor but it does not switch it. So a malfunctioning RM can never operate the sunroof motor.

Are your batteries still good? Maybe cranking drops voltage so badly the GM experiences a brownout and gets into an inconsistent state? This would only be the case if the problem occurs exactly when starting the engine. Your description of "start the engine and drive out" suggests it is some time after starting the engine.

Anyway, if your GM was never refurbished, consider to replace the electrolytic capacitors (or have them replaced). There's plenty of information about the subject in this forum.

[sofiabghome]

Revtor,

Thanks for the effort to reply.

I am not sure 100% if its RM or GM but this was the first stop to look over.

Both my modules were rebuild by Scott may be 10k miles ago. Batteries are like New full charge and also the
alternator is charing at full 13.7-14V New Bosch

Something happen and I believe I shocked the GM as say now or RM but leaning now to the GM as you say that
the signal/commands are coming from the GM to the RM.

Also the wiper blade mechanism is very clean and not rusted at all. I also forgot to mention that the wiper blade has
1 speed now since this all happened, washer pump all works as it should.

I am afraid that I perhaps burned a transistor or something...? but have nothing to lose at this moment rather than
replacing the capacitors with New again and check the system see if fixes this issue.

Alarm everything works fine so all other components are operating as it should.

Remember not while cranking. The engine fired up to 700rpm and immediately after I pushed the arm down and
hold it....because I know it takes about 2-3 seconds for the wipers to receive the power and start operating.

But the fact that all the windows as a function do open all the way just like you would do with the Key is crazy. E32
E34 have this option as well I remember when I was a kid on E34M5 1990 a friend showed me this. The idea was when
its parked on the sun and its very hot day before you get into the car you can open them all so that the heat to vent out.

Where is this option/coded located ? is it in the GM or ?

Thanks,
Anri

[revtor]

Did you have this problem with the windows multiple times? Or just that once. Maybe it was just a glitch from reconnecting the batteries? I know it does not sound reassuring, but if the issue does not come back...

Opening the windows with the key in the door lock is controlled by the GM but there are no coding options for this. It is standard behavior on all E31. But regardless of the coding options, it should not do this by itself.

If you can reproduce the problem(s): Is there any chance you can borrow a GM from a fellow E31 owner? Just to test whether the problems are with the GM.

PS: If you want to drive the car in the meantime without having the wipers in the middle of the windscreen, you can use E31 GM Coder to disable the wiper parking: Download the (existing) coding, set "Park wipers when off" to "No" and upload the new coding. After coding switch off ignition for ~10 seconds, switch on again and run a wipe cycle. The wipers should now "park" at the lowest point of a normal wipe cycle (slightly above the parking position). If you want to re-enable parking, just repeat the instructions but set the option to "Yes".

[sofiabghome]

pRevtor,

The issue with the windows sunroof is constant started right after the wiper event meaning they never stay closed....
Ones I do ignition On and close the windows then it depends 1 time all open after let say 5mins or 1 hour
but no matter what they always open either while I will be driving or engine is off.

I do know what do you mean by saying "glitch" but did try to disconnect the battery and reconnected even after
days staying off and no help.

I will find a GM to test and see if this is the problem but likely is.


Thanks,
Anri