Many modern cars are now designed so that their lights are built as a
one-piece unit known as a cluster. These are easier for the manufacturer to
produce than the older type of light unit, which is fitted separately to the
However, removing, dismantling and repairing these units is sometimes more
difficult, and very often more expensive, than on the older type of light
The most obvious reason for removing the light clusters is if they have been
damaged after an
. Light clusters are almost exclusively used for the
rear lights and are in a vulnerable position in the event of an accident.
You may also need to remove the light cluster if condensation or water has
built up on the inside of the lens. This can be caused by water seeping past
the sealing weatherstrip or
. Alternatively, the small holes built into
the units to allow water to drain out may have become blocked, trapping water
If the light unit is left in this condition the water can soon develop into
a green slime which can cut down the brilliance of the light unit. The water
may also come into contact with the electrical connections in the light unit.
This will cause corrosion and eventually the electrical contact will be lost
and the light will go out.
Before starting work on the cluster unit find out which type you have
fitted, because this determines how you go about removing the light cluster
from the car.
New replacement lenses are often very expensive so it is worth checking
a local scrapyard for an old one. Remember, however, to buy the correct
lens because some may only
on the left- or right-hand side of the
If you find that just the bulbholder is at fault this can often be
bought separately if it is the detachable type.
Removing an old type cluster
Old and new types of cluster unit
The older type of cluster unit (right) often has its lens secured by
external screws and can be removed separately.
These units are often wired so each individual bulbholder has its own
connector, and you may be able to remove the bulbholders from the unit
without disconnecting the wiring.
The later type of cluster units (left) are a little more complicated to
remove. The lens cover can often be removed only from the back of the unit
which may require that the entire cluster be removed from the car.
In some cases the lens is
with the cluster casing, and if it
breaks you will have to fit an entire new unit.
Removing a new-style cluster
Remove any trim panels covering the rear of the cluster units in the
boot or tailgate. Disconnect the
and then the multi-plug from
the light unit.
Find and remove the fixing screws, bolts or nuts from the cluster unit
(3), noting if they are different lengths. Then carefully pull the unit out
of its aperture in the car body.
The most simple type of cluster has the lens cover held to the cluster
casing by small screws which pass through the lens. To remove the lens you
simply unscrew the fastenings. However it is worth taking a few precautions
The securing screws are invariably of the cross-headed type but they may be
either Pozidriv or Phillips. So make sure that you use the correct type and
size of screwdriver to remove them. They may have become corroded due to their
exposed location and if you use an incorrect screwdriver it is easy to strip or
even break off the screw.
If you find the screws are really tight, soak them with
allowing time for it to work in before trying the screws again. Once the screws
have been removed the lens can be lifted away.
Now look for securing screws around the cluster casing. If you see them, you
can remove the cluster simply by undoing them. But first disconnect the battery
and the wiring to the bulbholders. Then release the securing screws
and the unit should now lift out with the bulbs and their holders in place.
If you cannot see any fixings, or if you cannot at this stage disconnect the
wiring, then you will have to dismantle the unit further before you can remove
it. The procedure for doing this is the same as for the more complex type of
If you have removed your lens because it was dirty, or if you need to
clean up a second-hand replacement item, you can do this with soapy water
and an old soft toothbrush.
Gently scrub out all dirt and grime from the lens. The silver backing
around the bulbs can also be carefully cleaned in the same way. But take
care not to scrub this too hard or you may find the silvering will start to
Before reassembly make sure the inside of the lens and bulbholders is
The more complex type of cluster unit has its lens cover attached to the
casing from the rear. There are no exposed screw heads on this type and the
entire cluster unit will need to be removed from the car before the lens can be
removed or the cluster checked.
Open the tailgate or boot lid so you can see where the rear of the cluster
sticks out. The cluster will often be covered by a trim panel. Remove this
first to gain access to the rear of the unit. The covers are often held by one
or more simple wing nuts or turn buttons and can usually be removed by hand.
The section in your car handbook on changing the bulbs should tell you how to
Start by disconnecting the battery earth terminal as a safety precaution.
Look at how the wiring is attached to the cluster unit.
Older style units have individual Wires running to each bulbholder. You may
be able to pull out the bulbholders without having to disconnect the wiring. If
this is not possible label the wires as you disconnect them so they don't
become muddled on reassembly.
Later units use multi-plug connectors. These may be a tight push-fit and
simply pull off. Others engage positively on to the cluster casing and you have
to press in the small thumb tabs on each end of the connector to release
If the rear of the unit is not accessible, the wiring can only be
disconnected once you have unbolted and partially removed the unit from the
Find where the main cluster fixings are located. Vertical units usually have
a fixing at the top and bottom while horizontal ones have them at each end and
may also have one located at the top and bottom. The fixing may be a bolt or
screw which threads into the cluster unit or it may be small nuts which tighten
fixed into the cluster casing.
Remove the fixings and carefully withdraw the cluster from the car. You may
have to twist it to get it to come out of its aperture. Take care not to damage
between the cluster unit and the body as you withdraw the unit.
Disconnect the wiring at this stage if you couldn't do so before.
With the cluster now removed look at the back of the unit to find the
fixings that secure the lens. Undo them, noting if they are of differing
lengths, and if so note where they fit. The lens can now be separated from the
Take care when lifting the lens cover away from the cluster unit. It may not
have been moved for some time (possibly never before) and may be tight on its
Gently tap it with your hand to break any bond that may have formed between
the lens and sealing gasket. Then lift the lens up gently, making sure that you
do not tear the gasket behind as you do so.
If you find the gasket has become torn or perished you will have to buy a
replacement for reassembly. New gaskets should be available from your dealer
but if you can't find one you can use a sealing mastic carefully applied in its
place (see sideline overleaf).
The light units are reassembled in basically reverse order to dismantling.
Remember not to overtighten the lens or cluster securing fixings as they
usually screw into plastic, which easily cracks.
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may lie in the light unit itself.
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