The work will take about 1-3 hours depends on
how competent and how brave you are.
First of all, I just
want to say that most of the instructions below were not written by me. Most of
the pictures were not taken by me. The credits belong to the original writer.
SUBJECT
Doors Will Not Unlock Using the Key Fob or
Central Locking Button
MODEL
E90, E91 (3 Series) produced up to 11/2008
SITUATION
One or more of the doors may not unlock when
using the remote key outside the vehicle, or the central locking button inside
the car. It is still possible, however, to unlock the door by using the key in
the driver's door lock cylinder or by pulling the door handle on the inside of
the car.
Typically fault codes A6D4 and A6D5 are
stored in the Junction Box Electronics (JBBF).
CAUSE
This is due to a blown fuse in the JBBF
caused by either:
An excessive amperage draw by one of the door
lock actuators, which is commonly attributed to silicone contamination; or
An intermittent, but acceptable, amperage
spike slightly above 15A, due to normal variation in the locking system.
CORRECTION
Replace the fuses 56 and 57 with one of a
different rating-20A.
NOTE: Never spray any silicone products into
the latch, as this will lead to premature failure.
PROCEDURE
Inspect fuse 57 (up to 9/07 production) or 73
(from 9/07 production) in the JBE.
Replace the blown 15A fuse with a 20A fuse.
Perform a function test by activating the
door locks 10 times in succession via the central locking switch.
NOTE: The thermal protection will be
activated after about 15 successive activations and does not indicate any
damage to the system.
Carefully observe the operation of each lock
actuator while it is being cycled. Lock actuators with some degree of damage
will exhibit noticeable symptoms of this, such as slow operation, abnormal
noises, etc.
If either one of the front door lock
actuators is determined to be the source of the blown fuse, both front door
latches (which contain the lock actuators) should be replaced per Repair
Instruction REP 51 21 090. For this replacement, the door latch kit, which
contains both the left and right side latches, must be used.
If either one of the rear door lock actuators
is determined to be the source of the blown fuse, only that single faulty latch
should be replaced per Repair Instruction REP 51 22 090.
If one of the front lock actuators and one of
the rear lock actuators appears to be faulty, both front latches and the single
faulty rear latch should be replaced per Repair Instruction REP 51 21 090 and
REP 51 22 090.
If no faulty lock actuators can be
identified, wait 2 minutes and then repeat step 4.
NOTE: If any door latches are to be replaced,
the attached procedure should be utilized in conjunction with the REP noted
above. This attachment will reduce the amount of time necessary to perform the
replacement.
After the second functional test, if no
faulty lock actuators can be identified, none of the latches should be
replaced.
PARTS INFORMATION
51 21 7 263 086
Door latch kit (contains both left and right
latches)
51 22 7 060 295
Door latch – left rear
51 22 7 060 296
Door latch – right rear
61 13 6 942 071
20 Amp mini fuse
The tools used are pictured below.
·
The window was brought down so that about
4-5" OPEN
·
Disconnect the battery
·
The "wood" trim
was removed using the plastic trim tools starting toward the inside
(right-hand-side of the photo). Pull the trim from the side closest to the
hinge since the other side (the side closest to the door lock) is a hook.
·
The three Torx-20 screws were removed from the
panel. These will fall out once you unscrew them all the way, don't worry if
they don't, they'll fall out once you remove the panel.
·
To remove the door panel I
started toward the top inside corner near the window speaker (right-hand-side
of the photo), again using the plastic trim tools. I worked clockwise until all
that remained was removing the panel from the upper clips. The fasteners hold
up well as I removed the panel a number of times. Once the panel was removed
over the unlocking button, the wires were unplugged, and the Bowden cable was
unhooked (see photos). The tape in the picture of the black interior
is where the hooks are. Make note of where each cable goes. There are five
cables: speaker, mirror, and window control, flood light (bottom of door) and
door handle hook.
·
The unlocking button rod
was pulled straight out of the actuator.
·
The power cable to the
windows has press-point and rotating lever to get it unhooked from the panel
(see photo).
·
The vapor barrier was
completely removed. It goes back on nicely. Use a sharp blade to help you cute the sticky
butyl tape. You don't want it all bunched up and messy when you put it back
together.
·
No special tool was used to
unhook the window glass from the window regulator. I just used the plastic trim
tools behind the glass to pry the clip out enough to pull the glass up. See the
photo with the circular hole in the glass to see what you're dealing with. This is the tricky part. There are two hooks that you'll need to unclip. If
you find that you don't have enough space for your hands to go in and out to
unclip the window just reconnect the battery and power window cable and play
with it to move the window to a comfortable position. TAPE the window glass to
the top of the door so once you unclip it, it won't fall down and shatter the
glass, I doubt this will happen but better to be safe. I have small hands and
after 30 minutes, I was able to unclip both holes. This is the WORSE part out
of this entire DIY. If you have big hands you're pretty much screwed. To get a
good idea of where the hook is, look down into the hole of the glass, you’ll
want to take your right hand position it behind the glass, grab the plastic
clip and pull outwards and using your left hand, pull/push the glass upwards to
unclip.
·
Once the glass was out, I
removed the two 10 mm nuts holding the outside window regulator guide to clear
some space. You can't really remove the window regulator,
just remove the two nuts and gently stuff it down and to the left out of the
way. The tension cables will still be intact so it's kind of tricky to move it
around, but as long as it's down as far as possible you'll have enough space.
·
The door lock was removed
by removing the small circular cover on the side of the door and removing the 4
mm Allen bolt. As far as I can tell, you must remove this first or the actuator
will not come out. This is referring to
the keyhole piece. The Allen bolt should come out all the way, be careful it
doesn't drop inside the door panel.
·
With the door lock out you
can reach up from the inside of the door and unclip the wires from the
actuator. There are two: one is on the bottom; the other is on the side. The
wires are tied to plastic plugs that are pressed into supporting holes on the
actuator. You can see these a bit in one of the photos showing the exterior
door handle cable.
·
To unhook the exterior door
handle cable from the actuator reach from the inside of the door and grab the
white plastic end and pull it out of its slot in the actuator. The second point
of attachment should come off the actuator lever at the same time (see photo of
cable end). Be sure to get both of slotted attachment points back on properly
on the new actuator and confirm that the exterior handle works before closing
things up. Aside from the exterior door handle cable,
there was another plastic clip that was attached to my actuator with no purpose
other than to route a cord out of the way of the window I suppose. These was
hard to remove, you just have to yank and twist it out.
·
I then removed the actuator
by removing the three Torx-30 screws.
For comparison I've shown the old (left) and new (right) actuators from several angles. Also shown is the actuator and door lock, showing the point at which the door lock enters the actuator.
Once you take the defective actuator out, you'll be confident enough to remember the steps to put everything back together. Just to make sure, I checked that the actuator was fixed before I placed the door panel and vapour barrier back on.
For comparison I've shown the old (left) and new (right) actuators from several angles. Also shown is the actuator and door lock, showing the point at which the door lock enters the actuator.
Once you take the defective actuator out, you'll be confident enough to remember the steps to put everything back together. Just to make sure, I checked that the actuator was fixed before I placed the door panel and vapour barrier back on.
