Jaguar XJ6 (X300) Rear View Mirror Leaking, Auto-Dim
The X300 auto-dim interior mirror is an electrochromic cell filled with gel, and with age it bubbles, goes cloudy, stops dimming and then leaks. The cure is a replacement mirror, not a repair in the car. I'd get it off before the gel reaches the console, photograph the mount and the plug, and choose a replacement that matches both.
How bad is it · Safe to drive
Safe to drive, but deal with a leak straight away
A failed cell still works as a plain mirror. The gel is caustic and permanently marks the plastic around the gear selector and the leather below it.
Which one applies to yours depends on your symptoms, your model year and what has already been done to it.
Likely causes, most common first
Read the check cost before the odds: a free check that rules a cause out beats a likely guess that costs money.
The electrochromic cell has failed
The dimming layer is a thin film of gel between two glasses. Heat and age break the seal, so the gel dries out, separates or escapes. A bubble or a cloudy band is the first sign; a leak follows.
A clear bubble after a hot day, a cloudy or tinted band across part of the glass, the green light on but no dimming, or oily drips onto the console.
Look at the glass in daylight for a bubble, haze or a line where the tint stops. Check the trim below the mirror for sticky marks.
Replace the mirror. The mirror maker, Magna Donnelly, once replaced these free under a lifetime warranty against a claim form with photos of the mount, the front and the connector; that offer has come and gone, so ask, but don't count on it. A specialist rebuild, a new mirror from the maker or a Jaguar dealer, or the Acura mirror 76400-SEP-A02ZA on later cars also cure it. A specialist exchange or rebuild service is the cheapest proper cure; send the old mirror back as the core.
A worn slider on early mirrors
Mirrors up to about mid-1996 set the dimming level with a slider on the frame. Its contacts wear and leave dead spots, so dimming works at some positions and not others. Later mirrors have a simple on/off button.
The green light comes on only at certain slider positions, and the mirror dazzles you at others.
At night or with a torch, run the slider end to end and watch the green light. Dead spots near the centre are typical.
Worth fitting a later button-type mirror; the slider type can't be rebuilt.
An intermittent light sensor
The mirror compares the light ahead, through a small hole in its back, with the glare from behind. If the sensor or its contact is intermittent, dimming comes and goes although the cell is fine.
It dims some nights and not others, with no bubble or leak. Tapping the mirror may bring it back.
With bright light from behind, cover the small hole on the back of the mirror with a finger. If it dims then, the cell and its supply are good and the sensor side is suspect.
Worth replacing the mirror; the Acura type on later cars is the cheap route.
A replacement mirror wired to the wrong pins
The car needs three wires to the mirror. A mirror from a later car may have six or seven, for auto headlamps or a rain sensor, and the colours don't always line up. Wrong pairing leaves a good mirror dead.
A new or second-hand mirror never lights its green light, or never dims.
Compare the mirror's lead colours with the car's three wires before you join anything. Early 1995-96 cars didn't all have the auto-dim mirror at all, and a mirror from a 1998-on car is a different part, so give the year and the controls on the mirror when you order.
Join white to white and black to black; on some cars the mirror's grey goes to the car's green. Tie off any extra leads. Moving the pins into the old Jaguar connector is more reliable than splicing.
No power to the mirror
The mirror shares its feed with the cigar lighter fuse and the interior lighting circuits. If the green light never comes on, the mirror may simply have no supply.
No green light at all, especially if the clock, lighters or interior lamps are out too.
Meter across the black and white wires at the mirror plug with the ignition on: 12 V there and no green light means the mirror; no voltage means the fuse or the feed.
Replace the fuse that also feeds the cigar lighter; if the interior lamps and clock are dead too, trace that common feed first.
The order to check them in
The point of the order is money: each step either rules a cause out or makes the next one worth doing. Green is free, amber costs a little, red is the one to arrive at last.
Catch the gel now
If the mirror has a bubble or is dripping, put a cloth on the console below it and wipe any gel off at once. It eats the plastic around the J-gate.
freeWatch the green light
At night or with a torch from behind, switch Auto on. No green light means power or wiring; a green light with patchy dimming means the slider, the sensor or the cell.
freeCover the sensor hole
With light from behind, put a finger over the small hole on the back of the mirror. Dimming then proves the cell works.
freeMeter the plug
With the ignition on, look for 12 V across the black and white wires. Without it, check the fuse shared with the cigar lighter in the fuse box in the rear footwell.
freePhotograph the mount and the plug
Early cars use a twist-on cam mount and later ones, 1997 for example, a rectangular wedge pedestal. Note where the cam sits, how many wires there are and their colours. A replacement that doesn't match both won't fit.
freeTake the mirror off without cracking the screen
Turn the plastic screw at the back of the overhead console a quarter turn and let the console hang. Unplug the mirror, prise off the small cover on the base and slide the base straight off the pedestal along its guides. Never lever it at an angle, and work with the screen at a normal temperature.
freeChoose the replacement
Ask the mirror maker about the warranty first. Otherwise a specialist rebuild, for example about USD 45 to 95, or a new mirror, for example about USD 250 from a dealer. On mid-1996 and later cars with a three-wire plug and the rectangular mount, the Acura mirror 76400-SEP-A02ZA fits once the Jaguar plug is transferred; it won't suit the round cam mount or a seven-wire plug.
about USD 45 to 265The fuses named above — where they sit
The highlighted position is the one the procedure talks about. Pulling a fuse is a stop-gap, never a repair: check what the circuit feeds before you pull it.
Circuit descriptions from the Jaguar fuse tables, 1995 edition. Drawing by jagaux.com from the factory electrical guide. Fuse layouts change between model years — read the legend on the lid of your own box before pulling anything.
What it usually isn't
Don't spend money here first:
If none of this finds it:
On jagaux.com
- Jaguar XJ6 (X300) Steering Column and Memory Seat ProblemsIf the door mirrors won't move or don't return to their memory positions.
- Jaguar XJ6 (X300) Instrument Cluster, Dash LightsIf the clock and dash lighting are out along with the mirror's green light.
- XJ6 (X300) fuse boxes and relaysThe cigar lighter fuse that also feeds the mirror; 1996 and 1997 from the same page.
- Jaguar VIN decoderConfirm your exact model year, engine and factory options before ordering parts — free.
Ratings, fuse numbers and torque figures vary by model year and market. Read the legend on your own car before pulling anything, and use the figures in the manual for your car, not the ones in a video.
Check your VIN: exactly which car you have and which bulletins apply to it.