Hello my name is Danny Hopkins and I'm
here at Britpart in Shropshire with
managing director Paul Myers hello
hello here we have an electric park
brake module which is obviously broken
there's another video in this series
which shows you how to replace that
module as a single unit but Britpart
have just come up with a clever solution
which means you don't have to do that
correct yes on the discovery 3/4 and
Range Rover Sport where normal failure
mode on these is the plastic gears
strip when the cable seize instead of
replacing the whole module we've come up
the kit of the gears and a hardware so you
can just replace with four broken
components brilliant okay well let's go
into the workshop and see what Martin
can make of this himself
okay let's have a look at the bits to
get in this rebuild kit first of all set
of gears which are the main failure
points in the park brake module you also
get two rubber mounting bushes which
almost always break when you remove the
module from the car
and finally a new set of Torx screws
because the originals are probably gonna
be rusty and they might round out so
this is the module as you will have
removed it from the discovery the first
thing to do is to lay it down and undo
the original screws that hold the front
plate on and for that you need a t20
Torx as I said before it's likely that
the screws are going to be quite rusty
because this module spent its whole life
underneath the discovery getting blasted
with mud and salt and all sorts so if they
need it just clear the heads out wire
brushing any debris out so the t20
bit goes all the way in once you've got
all the screws undone you might take a
bit of effort to just prize this front
plate off because it's a stuck on with a
lot of silicone to stop water getting
inside the module so with that out of
the way and we can see the inner
workings the first thing we need to do
is release the cables so they've got
these big plastic nulled nut things on
the side you undo
each of those they normally come undone
by hand one cables held in with a
quick-release clip and the other one we
need to unthread because it's threaded
it into the end of the pool so if we
start by undoing these just move each
cable to each side so the first one
we're going to release is a threaded one
so if we ease the cable outer off the
inner we can then twist this adjuster
here and thread the cable out of the
mechanism when we refit this cable we
need to make sure it goes back into the
mechanism exactly five turns it's also a
left-handed thread so you need to turn
it clockwise to release it so that's
that cable released and pop that aside
move to the next one to release this
cable we need to slide the mechanism
over and there's a little plastic collet
that holds the cable to the end of the
mechanism so just use a little pick to
depress the clip so just use a pick to
depress the clip just collet will slide
back off there and the cable will be
released like so we can put this cable
aside as well next up we need to
disconnect circuit board and the two
terminals on the motor so that we can
then access the gearbox so note which
color cable goes to which terminal on
the motor so there's a red and a blue so
once the motor is disconnected just need
to undo this single blue connector on
the circuit board again just slides out
under a little bit of pressure tuck that
aside so with the circuit board
disconnected just need to release these
three Torx screws and then the gearbox
will come out of the casing
okay three screws are out so now the
motor and gearbox assembly will lift out
along with the cable pull so just once
that's released slide the gearbox
complete with the motor off the end of
the pool and leave that inside the
casing retrieve the two screws and now
we can take this apart and replace the
gears the gearbox is held together with
more Torx screws four in total so just
take our driver again
release them
okay next the two halves of the gearbox
can be separated like so just pulls
apart we can see the gears inside the
motor can stay attached to this side of
the plate so we can place that aside and
now we've just got to replace the three
plastic gears so start with this one
slides off its shaft like so and this
has got a clutch mechanism built in
which we need to transfer over to the
new gears so we'll do that one last next
this is its other small gear bring that
one out place that aside and last this
larger gear which sits inside a big
bearing on the inside of the housing so
obviously if you've had failure of the
original gears you'll need to look
inside this case and make sure you clear
out all of the debris any broken gear
teeth or floating around in there and
also reapply a bit of grease before you
build the new gears into the casing so
when you do go to build the new gears in
the first one you're gonna fit is this
large one which is an interference fit
in the big bearing in the back of the
housing so push that one in and it's an
idea to have a look at this side to make
sure it's going into the bearings
squarely that will just push all the way
home make sure when it's in place that
it turns smoothly like so the next one
to fit is this gear this the next small
gear no it's not this one the next gear
to fit is this small gear this just sits
into place in this corner and you'll
notice that the pin that that gear spins
on stays on this half of the gearbox
housing so it will just float around
until you go to refit this plate finally
okay so the final gear has this slipper
clutch mechanism built in which
comprises is
a washer and an e clip and we need to
swap those items over to the new gear
before we fit that to the case now you
can take your bag that your parts came
in lay that over the top of the gear and
then use a screwdriver to pop the e clip
off because if you don't do that there's
a real possibility when you release it
parts will go everywhere and you'll
never find them ever again
so with that released we can remove the
e clip the washer and the spring get rid
of that old gear get the new gear and
then it's just obviously a case of
stacking them back on this gear in the
opposite direction they came off so when
you build up the new gear it spring goes
on first and then the washer and you
need to compress that spring while you
get the e clip in place so push it down
by hand get the eclip push it into its
ridge on the gear and then you need a
pair of pliers just to clip that into
place it's a bit fiddly but there we go
you hear the e clip clip into place make
sure it's properly home and now that
gear is ready to go back into the gear
box the gear goes into the gear box with
the slipper clutch end pointing
downwards so take that last gear push it
into it spin all the way down make sure
it turns nicely and now we can refit the
gear box end to cover again this pin has
to pass through the second gear that we
fit it to the gearbox so can be a bit
fiddly to line up so just take the
gearbox cover like that give it a bit of
a wiggle make sure everything aligns
and it should slide into place like that
and the edges of the casing should sit
flush if everything's in the right place
then it's just a case of putting the
four screws back in to fix it all
together
that's the gearbox back together and now
that can be refitted to the electronic
park brake module and we can finish
rebuilding so take your gearbox and the
pool slide it through that Center gear
like so a line up the mounting points so
that you can fix the gearbox back in
place with the three screws
I'd say it should all fit in there
nicely
secure the gearbox back in place I think
once those three screws are nipped up
you can then reconnect the circuit board
just with the single blue connector like
that and clip the spade connectors back
onto the motor terminals and now we can
reconnect the cables so take the
quick-release cable first feed it in
through the side of the park brake
module and you'll notice there's a small
peg on this plastic disc that must slot
in once you've got it in place take that
nut and loosely start it because we
still need a bit of room to maneuver
this into place so pick up the
quick-release end and attach it to the
end of the pool it'll just slide over
once that's in place just slide the
plastic collar over the whole lot and
that will keep it locked in position so
it's slid over the inner cable and the
outer collar give it a push and it just
clicks and that will now hold the cable
onto the end and we can finish
tightening this so just finish
tightening this and then we can move on
to the other side again this is a
threaded cable we need to thread this
into the pool five turns and then don't
forget it's a left-handed thread so
you're essentially turning it
anti-clockwise to tighten it up so feed
it in through the side of the module get
it started
and then turn that one two three four
five turns once that's latched in take
the plastic collar push it into the side
of the park brake module making sure the
pin lines up like so should sit flush
and then take this wheel hand tighten it
like that now we can put a bead of
silicone around the edge of the module
to stop any water getting in and refit
the cover so just use some normal this
is black silicone just put a thin bead
around the edge just to keep any water
out it's quite difficult to get on there
evenly because the edge is so thin once
it covers in place it'll all spread out
and it'll seal up fine so just spread
the silicone around a little bit if you
need to to make sure all the edges of
the module are covered once they've got
a thin bead you can take the top cover
again just offer it up into place make
sure all the screw holes line up push it
down and now if we can use our new
screws to fix that into place to
permanently
so when all the screws are tight the
module is ready to be refitted to the
car and the replacing the gears is a
really cost effective way of fixing a
really common problem on the Discovery
3 we've covered how to remove and
refit the electronic park brake module in
another video in the Britpart workshop
series
