Jaguar XJ-S. Manual - part 159

 
 

631

 NUMBER WATTAGE 

 756  1.12W 

 1813  1.44W 

 1892  1.73W 

 1815  2.8W 

 1891  3.36W 

 1889  3.78W 

 1816  4.29W 

 1893  4.62W 

All of the above bulbs are bullet-shaped; the glass capsule is about the same diameter as the base.  For places where 
space isn’t a problem, there are also the following miniature bayonet bulbs with a larger spherical glass capsule: 

 NUMBER WATTAGE 

 57  3.36W 

 257  3.78W 

 1895  3.78W 

 293  4.62W 

The 1895’s are sometimes available in colored versions. 

If you visit a marine supply store, you will find an assortment of high-power miniature bayonet bulbs.  In addition to 
reasonably-priced 12V5W bulbs, there are some atrociously high wattage bulbs with proportionately large glass 
capsules, up to 20 watts.  There are also some halogen bulbs in 5W, 10W, 15W and 20W, some of which are a little 
odd-looking but they are all about the same physical size as the tiny bullet-shaped bulbs.  Some of them aren’t even 
labelled halogen, but rather labelled only for some particular application, a depth finder or something.  Of course, you 
can tell they’re halogen by the price.  As a bonus, all of the bulbs sold at a marine supply store are corrosion-resistant 
for marine use. 

 

FIBREOPTIC SOURCE BULB:  This bulb is a miniature bayonet type.  The bulb charts in the Jag manuals list a 254 
or 989, depending on which book you look at, and describe it as 5 or 6 watt, again depending on which chart you 
believe.  254 is a festoon bulb, so that’s wrong. 

Note that 5 or 6 watts is high wattage indeed for a miniature bayonet; the 6 watt is higher than any in the chart above.  
Clearly, this particular application requires some serious light.  Either the 1893 or 293 listed above probably fits the bill 
as 5 watts, meaning you’ll get satisfactory light.  If the various things lit by the fiberoptic source have always been too 
dim for you, though, a visit to the marine supply store may be in order; one of those 5W halogen bulbs might be just the 
ticket to liven up that dash.  Going to much higher wattage than recommended would probably melt the fibreoptic unit 
housing, so don’t get carried away. 

 

SIDE MARKER BULB:  In the US and some other countries, the lights on the front and rear ends of the car are 
required by law to be visible from off to the side of the car.  The taillights on the XJ-S meet this requirement, since they 
wrap around the corners.  The front markers are in the bumper, however, and therefore cannot be seen from the side.  
To meet the requirement, a separate side marker light is provided just forward of the front wheel on each side.  On the 
SI/II/III saloons, the lights on either end don’t wrap around the corners, so there are separate side markers on both ends. 

 
 

632

The side marker on the XJ-S takes a miniature bayonet type bulb.  The bulb charts in the Jag manuals list a 207 or 233, 
depending on which chart you look at, and describe it as 5 watt.  This author’s ’83 was fitted with bulbs labelled 233 
and 12V4W. 

Several of the bulbs listed above would make suitable substitutes.  If you don’t really care how bright your side markers 
are, you can replace these bulbs with different wattage bulbs; however, you need to be concerned about whether the 
park lamp failure sensors work properly -- see page 597.  These side marker lamps are monitored by the same park 
lamp failure sensors as the front parking lamps, and reduced wattage bulbs may result in bulb failure indications on the 
dash.  If you wish, the sensors can be adjusted for the new current level. 

Judging from the typical condition of the original bulbs, the corrosion resistance of marine bulbs might be helpful in 
these side markers. 

A piece of 5/16” hose may be helpful in getting the side marker bulbs in and out. 

 

CIGAR LIGHTER BULB:  One bulb chart in the Jaguar repair manual says the miniature bayonet bulb for the cigar 
lighter (643) is 22 watt.  I don’t think so -- it should say 2.2 watt. 

 

BAYONET BULBS:  All the bulbs in the pre-1991 taillights and front turn signal housings are bayonet type, although 
some are single-filament and some are dual-filament. On the dual-filament bulbs, one pin on the base is positioned 
differently than the other to ensure you install it correctly.   

 

REAR TURN SIGNALS, BRAKE LIGHTS:  In the US, for these applications calling for the single-filament bulb 
number 382, use the 1156 -- very common, can be found in any auto parts store or Wal-Mart. 

 

FRONT TURN SIGNALS:  The bulb chart on page 04-3 of the ROM ©1975 calls for GLB 380, describing it as 
“Double filament - Italy only”.  It lies; it should say US/Canada only, Italy uses the single-filament 382.  Among the 
electrical diagrams following Section 86 of the same book is another bulb chart, and this one describes the GLB 380 as 
21 watts, when it should say 21/5 indicating that it is a dual-filament bulb. 

In the US, for the dual-filament 380, use the 1157 -- perhaps the most common taillight bulb there is. 

Another common -- and very similar-looking -- dual-filament taillight bulb in the US is the 1034.  If you try to use 1034 
bulbs in the XJ-S, the indicator on the dashboard may only light the first blink, or not at all, when you operate the turn 
signals.  This is the bulb failure indication for the turn signals.  Since the 1034 bulbs are lower wattage, the reduced 
current causes a bulb failure indication. 

If you want brighter turn signals, J. C. Whitney (page 691) offers a 30/8W halogen 1157 bulb, catalog number 
81xx0439B, that they claim is 50% brighter than the standard 1157. 

 

TAILLIGHTS:  In the US, for the taillights (smaller bulb on the outer corner of the taillight housing), use number 89 
even though it’s slightly more powerful (8W) than the 5W number 207 specified in the charts. 

 

FESTOON BULBS:  Festoon bulbs are the tubular bulbs with a pointed connector at each end.  Here in the US, they 
are described as “SV8.5mm”, 8.5mm being the diameter of the connector at the end.  In addition to the wattage, you 
need to pay attention to the overall length measured from point to point.  There are at least two different length festoon 
bulbs used in the XJ-S, 1.45” and 1.75”.  Sometimes festoon bulbs are clamped at the ends while other times they are 
held by the points; in some cases below, I mention which method is used. 

 

 
 

633

BOOT LAMPS:  The XJ-S used miniature bayonet bulb number 989 in the trunk up to 1982.  From 1982 on it used 
festoon bulb number 239 (5W).  The overall length of this bulb is 1.45”.  In the US, 11004 is a perfect replacement. 

Note that the 1982-87 Hella boot lamp assemblies are not symmetrical, although they appear to be at first; the bulb 
itself is held closer to one side of the lens than the other.  The lamp should be installed so that the bulb is held farthest 
away from the center of the trunk.  This fixture holds the bulb by the points. 

From 1987 on, the same lamp assemblies were used in the boot as in the interior. 

 

INTERIOR LAMPS:  The Jag bulb charts say the interior lights are either number 272 (10W) for early cars and 254 
(6W) for later cars.  Other sources offer 265 for cars up to VIN 100349 and 239 for VIN 100350 onward, 
corresponding to a change in the fixture itself.  265 is apparently 1.75” long, while 239 (the same bulbs as the boot 
lights ‘82-on) is a 5W bulb 1.45” long. 

If you have an earlier car with 1.75” bulbs and want 10W replacements, you can buy GE bulb number DE7576.  There 
are also bulb numbers 211 or 212 that will physically fit, but the wattage is unknown.  211 bulbs are also available in 
pretty colors, if you want to get tricky.  10W 1.75" festoon bulbs are also available in marine supply stores. 

If you have the later fixtures and a 5W bulb will do, the 11004 will work.  If you want to try a 10W, there is also a 
11005 available -- but you might want to keep an eye on them that they don’t melt the fixture. 

The later lamps (all four corners of the interior use the same fixture) clamp onto the ends of the bulbs. 

 

ROOF LAMP:  The bulb in the roof lamp is supposed to be 10W, and is 1.75” long.  The Jag bulb charts seem to leave 
the number column blank, but other sources suggest number 265 here.  This atrociously expensive Hella fixture holds 
the bulb by the points.  The GE bulb number DE7576 is a perfect replacement. 

 

BACK-UP LAMPS:  The books say the bulbs in the back-up lights are number 273, 21W.  You can also find similar 
bulbs in 18W; close enough, especially if you replace both together.  These festoon bulbs have a total length of 1.75”.  
The glass portion itself is also much larger in diameter than the connectors, giving it a bulged look. 

Either the 18W or 21W bulbs are hard to find in the US; you will probably need to find a place that specializes in 
import light bulbs.  One alternative is the marine supply stores, which carry a 15W bulb the same shape and size.  Or, 
you could substitute the non-bulged 10W 1.75” bulbs commonly available and call it a day. 

 

LICENSE PLATE LAMPS:  The license plate lights require festoon bulbs 1.45” long.  The Jag bulb charts call for a 
254 (6W), but other sources offer the 239 (5W) for this application.  If 5W is acceptable, the 11004 bulb will serve.  
You can go up to the 10W 11005, but I’m betting you’ll melt the lens. 

 

CAPLESS BULBS:  What the Europeans call a capless bulb is called a wedge bulb in the US.  Capless bulbs have no 
base at all; the bottom of the glass capsule itself is formed into a flat edge and the wire conductors coming out of the 
capsule are wrapped around the edge. 

The following is a chart of some US wedge bulbs, 13-14.4V: 

 
 

634

 NUMBER WATTAGE 

 658  1.12W 

 160  2.66W 

(long 

life) 

 161  2.66W 

 158  3.36W 

 184  3.46W 

 124  3.78W 

 194  3.78W 

 196  3.78W 

 558  4.29W 

 192  4.29W 

 193  4.62W 

 168  4.90W 

 175  8.12W 

Numbers 168 and 194 seem to be the most readily available. 

There is another wedge bulb available in auto parts stores, number 3652.  This bulb looks exactly like the bulbs listed 
above, but it’s either a 5 watt short-life (only 700 hour) incandescent or a 5 watt halogen bulb, depending on which 
reference guide you’re looking at.  It does not say halogen on the package, but it does cost about five times as much as 
a 194.  It definitely produces a much brighter, whiter light than a 194 -- this author can vouch for that.  If it’s really a 
halogen, it will probably last several times as long as a 194 -- perhaps the life of the car. And if it’s really a halogen 
(and even if it’s not), it’d be a good idea not to get fingerprints on it when installing. 

Auto parts stores also carry a series of wedge bulbs that are physically much larger than the bulbs listed above but have 
the same wedge base.  They typically have 3-digit numbers starting with 9, such as 921.  These are much higher 
wattage than the small bulbs, up to 17 watts or some such -- you can check a catalog to find the wattage listings.  
Whether or not you can use one in place of one of the smaller bulbs obviously depends on whether you can physically 
fit it in the space, whether it will generate too much heat and melt something, and whether it will draw too much current 
for the circuit. 

There is also a halogen capless bulb of this larger size.  The number is 2040, and it’s rated at 8 watts. 

 

PUDDLE LIGHTS:  The door edge lamps, also known as puddle lamps, are a 5W capless.  They’re not even listed in 
the bulb charts in the Jag books, but the Haynes manual says it’s number 501.  US number 168 is perfect. 

The access is kinda neat; you remove one screw from the bottom, then slide the lens off rearward. 

 

INSTRUMENT PANEL LIGHTS:  The instrument panel illumination lamps are supposed to be a capless 2.2W, 
number 987.  In the US, finding a 161 would be good, 160 would be better.  Or, you could try something with higher 
wattage and hope nothing melts or burns up in there. 

 

INSTRUMENT PANEL ILLUMINATION IMPROVEMENT: John Napoli suggests you disassemble the pod, and 
clean all the dust out of the warning light boxes and the like.  “If you also want to improve lighting, remove the four 
green lenses.  The instruments will be that much more brightly lit at night.  You can probably also fit brighter bulbs, if 
you so desire.”