As promised, here's a write up on how to upgrade your XC90 form 1 Fog Lamp to Two Fog Lamps ....
Note : This guide is provided for information only, and refers to how I completed the project on my own car.
The part numbers quoted refer to my particular model of XC90,
and are determined by providing your Volvo dealer with your VIN number.
This guide and advice within it are offered “as is” - I am not a trained Volvo mechanic,
and accept no responsibility whatsoever if you attempt the project and anything goes wrong,
breaks, or doesn’t work etc. ! - You do so entirely at your own risk !
The aim of the project was to replace the existing rear ( n/s ) reflector with a Fog Lamp housing,
so that there would then be two Fog Lamps at the rear of the car acting together,
instead of the ( UK ) legal minimum of only one.
This guide relates to a RHD car, so a LHD Fog Lamp had to be purchased.
Similarly, if modifying a LHD car, then a RHD Fog Lamp would be needed.
Parts :
LH Drive rear fog lamp body ( 31213647 ) £21.80
Fog Lamp bulb socket / harness ( 8693010 ) £10.00
Bulb : BAY9s 12v / 21w
Tools :
10mm Socket & Socket wrench
Torx Screwdriver
Soft faced trim removal tool
Strictly speaking there is no need to remove the main light cluster,
but doing so makes access easier and reduces the risk of it becoming damaged !
It is best to perform this job on a warm day - plastic trim panels need to be removed and pried apart,
and if attempted when the plastic is cold and brittle there is a risk of it cracking.
From inside the rear cargo area remove the small corner piece from the floor
( it lifts straight out ),
and then remove the access panel which pulls outwards from the tab on its bottom edge,
allowing the panel to drop and free from the upper retaining tabs.
There are two elongated 10mm nuts holding the rear light cluster in place as shown :
Remove these and then gently ease the light cluster away from the body of the car.
The wires should be long enough for it to be turned to the side out of harms way.
The red and black fog lamp wires are now visible.
The body coloured trim panel - directly underneath the main light cluster,
now needs to be removed from the black plastic “box” that it is attached to.
It is held in place by lugs moulded around the edge of the trim,
and just pulls straight out towards the rear of the car.
It may need a little persuasion by gently twisting, flexing,
and prying around the retaining tabs with a suitable soft tool
so as not to damage the painted finish.
Once removed, the wiring socket into which the new Fog Lamp will be plugged is accessible.
This is a good time to check that the new Fog Lamp works by connecting it up to the socket before fitting to the car !
Assuming the new Fog Lamp works as it should, remove the existing reflector unit by inserting a flat bladed screwdriver as shown,
and gently release the retaining tab behind it away from the car,
allowing the complete reflector unit to be withdrawn towards the back of the car.
The “box” which has the wiring socket clipped to it, has a wiring channel at its rear edge,
running down into the void where the Fog Lamp is fitted.
The “box” is secured to the car bodywork and also to the inner edge of the bumper.
Unfortunately the wiring plug for the new Fog Lamp will not fit through channel unless the “box” part
is at least partially separated from the bumper, which would ordinarily require the bumper to be released from the vehicle !
It is possible however to partially separate the “box” from the bumper sufficiently to allow the cable plug to pass through.
Undo the 3 Torx screws as shown, securing the “box” to the car body work.
Noting that is best to do this on a warm day, as cold plastic is likely to crack when flexed,
CAREFULLY pry the lower edge of the box away from the bumper edge with a soft faced tool
so as not to cause damage to the painted finish, to release the locating lugs along the top edge of the bumper.
There is a plastic “shield” on one edge of the wiring plug, which locks into the socket when connected.
Begin to feed the wiring plug up from the fog lamp position into the channel, with the “shield” part facing away from the back of the car.
I found that the plug fits through the channel easiest this way !
Gently pry the bumper and “box” apart using suitable soft faced tools / levers,
at the same time as pushing the plug up into the channel from underneath, until the plug passes fully into the box.
Reclip the bumper to the “box” and replace the 3 screws securing the “box” to the bodywork.
Connect the wiring plug to the socket.
Replace the trim piece.
Insert a new bulb ( Type BAY9s - 12v / 21w ) into the bulbholder,
and fit the bulbholder to the Fog Lamp by lining up the three lugs
and twisting clockwise to lock in place.
The Fog Lamp can then be fitted to the car -
pushing it into the housing until it “clicks” as the retaining tab locks it into place.
Refit the main light cluster and tighten the 2 x 10mm retaining nuts.
Replace the interior panel cover and corner floor trim piece.
Job Done !
