How to make your side marker lights blink on Series 3, XJ-6 Jaguar

Part 1:
This easy modification will transform the Sidelights (the four side-marker lamps mounted on the side of each fender), so they will 'blink' with the front and rear Turn Signal Indicators and with the Emergency Flashers, as they do in the European version of the Series 3  XJ.  (the blinking European-style Sidelights were not used in USA cars, they are also smaller and more attractive than the US version).

This a Safety Mod considering the amount of traffic today: other drivers need to see your Turn Signals from every angle. Worse, in the Series 3 XJ, the Front Turn Signal Indicator assemblies are recessed deep into the bumper, so they cannot be seen from the sides of the car during daytime, and hardly at night, so other drivers cannot really see your intentions when they are by the sides of your XJ, not a safe situation to avoid a scare.

I am aware of a 'black box mod' invented by a member of Jag-Lovers but the contraption is complicated to install, requires drilling, mounting, routing wires through difficult cavities, and it doesn't even take care of the REAR Sidelights, only the Fronts, not to mention the $60.00 price, so I passed on it, though it was a fair attempt at solving the problem so many XJ owners complain about. I thought that a solution had to exist in the XJ's wiring itself, then I found it: a simple 1-wire modification to each Sidelight! You will love this Mod because of its simplicity and low cost in materials needed. I experimented with my XJ and after solving a few puzzles, it works! It costs around $5.00 in specific parts needed.

Materials needed:
1.) Two (or Four) wire Tap Splicers for 22 through 18 gauge wire, no need to solder anything with this mod, the Tap Splicers are safe and sturdy enough. package of four: $ .99  (see picture).
2) Bag of forty, 4-inch long, multi-purpose Nylon Ties; (you will use these in all 4 Sidelights and you'll be glad with the leftover ties). bag of forty: $ .99
3.) Four sections of 18-gauge wire: Two sections measuring 48 inches each for the Front Sidelights, two measuring 9 inches each for the Rear Sidelights. The wire insulation can be Green or Black, your choice, Yellow looks great!, but whichever color insulation you use, get the four new wire sections in the same color and make sure it is 18 awg. ( I had the wire, so nothing was spent here).
4.) Four plastic wall Anchors with 'shoulders', size 3/16" or 1/4" Inside hole Diameter. (for the Front Sidelights). These are the kind you insert into the wall, then insert screws into them, (used in wallboard); The "shoulder" prevents the Anchor from being pushed through the wallboard hole. The actual size needed may depend on the year your S3 XJ was made. Just get 4 of each size, they only cost about 6 cents a piece, and you might already have some laying around. bag of four: $0.29
5.) Four hard-Nylon Washers with a 3/16" or 1/4" center hole. (for the Front Sidelights). $0.50 all 4.
6.) Four Nylon Machine Screws size #8-32 x 3/4" long. (for the Rear Sidelights). $0.50 all four.
7.) Four Nylon machine screw Nuts size #8-32. (for the Rear Sidelights)  $0.50 all four.All the above material can be found in one trip at Lowe's or Home Depot in their Specialty Fasteners hardware aisle and Electronic Supplies rack, Radio Shack has some of these but not all
8.) Package of 10-Amp spare Fuses. (you'll blow three or four fuses testing this mod). $ 1.19 at any auto parts store.

Tools needed:
One small shop towel, electrical tape, wire cutters, phillips and flat screwdrivers, pliers, 5/16" socket and small ratchet. a light to illuminate the inside of the Front fenders.

These instructions are detailed for the do-it-yourselfer, no details are left to wonder about. Once you do the first Sidelight, you'll understand how easy it is.

Part 2

First Things First:
Park the car in a comfortable working place turning the front wheels to the extreme right or left, depending on which Front Sidelight you will modify;  You will be working outside and inside the Front fenders; Removing the tires from the car is not necessary.  I recommend you do the Driver's Sidelight first, (left side), it will be easier than the Front Passenger side and you will see why later, so turn the front tires to maximum right because the experience gained on the Driver's side will help you complete the Passenger side in half the time, (the passenger side front fender has the Charcoal Canister and all the hoses there, so No Smoking, there are fuel vapor components in that area).

1.) Remove the Phillips screw from the Amber plastic lens on the Driver's side Sidelight, remove the lens and foam gasket, (don't remove the bulb), put those parts on top of the front bumper for safety.  (TIP: If your foam gaskets are deteriorated, you can make new ones from foam insulation pads (gaskets) used behind Wall Switch covers and Wall Outlet covers, sold at Lowe's or Home Depot, the material is the same. You'll need a package of the Wall Switch gaskets, since they have the most gasket material without holes or cutouts, then you can trace the lens over the foam pad and cut with scissors 1/16" inside the trace line, because the old gasket has probably shrunk).
2.) Bring the light behind the fender to illuminate the area;  Remove the two nuts and washers behind the sidelight. In my car the nuts are 5/16",  in some XJ they are 10mm.  Put those near the other parts you just removed.
3.) Carefully pull the Sidelight assembly and its black rubber gasket off the fender, gently pulling the 2-wire Harness through the large round hole to the outside until you can see the connections at the rear of the Sidelight assembly; Wrap the Sidelight body/assembly in the shop towel so no accidental damage is done to the paint by the two studs in the rear of the Sidelight body.  Keep the towel in place with electrical tape or a rubber band, don't cover the bulb and the harness connections, but keep them away from touching the fender or the bumper's chrome.
4.) go to the Front Bumper (driver's side):  Remove the two Phillips screws from the Turn Signal/Parking Lamp assembly, then pull the assembly forward (or pushing it from behind) and unscrew the Bulb socket behind it by turning it one way or the other, remove the amber Lens assembly and put it and the screws on top of the bumper. (aren't you glad old XJ have real Bumpers?).  Push the Bulb socket assembly and harness back out through the aluminum bumper-cutout and let it hang below the bumper. Don't remove the Bulb, but this will be a great time to check and renew all those bulbs, even if they seem 'good'.  From now on this mod is going to make all blinking bulbs work more than before so any weak bulb will expire sooner.

Go back to the Sidelight; Observe that the Sidelight wire harness has two wires connecting to the Sidelight bulb Base or 'hub'. One of the wires is Red, and the other wire is Black. Observe that the Black wire is attached to the SIDE of the bulb base/hub with a 'bullet' type of connector which goes inside a 'barrel' attached to the Bulb base by a ground 'lug'; That Black wire is the Ground/Earth/Negative wire for the Sidelight; Now check to see if you can move the Black wire's 'bullet' inside its 'barrel' holder, they become loosened with age and this is exactly what you are looking for. If you can move it or turn it, then it can be removed easily, so remove the 'bullet' from the barrel by gently pulling it or pushing it back from the opposite side of the bullet until it comes out from the barrel in one piece. The Red wire goes through the rubber base-cover and makes contact with the bottom of the bulb, that is the Hot/Sun/Positive wire. -All four Sidelights are wired identically- Leave the Red wires alone, they will not be modified.

You will remove the Black wire's 'bullet' connector from the Sidelight asembly 'barrel' at all Four sidelights but only one at a time as you go. Follow the next instructions to the letter.

Part 3

After removing the 'bullet' from the 'barrel', remove the Black wire from the bullet by pulling it, it should come off. Now seal the exposed end of the Black wire with Electrical tape, because that Black wire will not be used again, it needs to be sealed and isolated from making accidental contact with anything from now on and in the future. Also for posterity, if someone should want to go back to non-blinking Sidelights, they can simply reconnect the wire to the bullet and then to the barrel. Once you seal the 'bullet' with tape, fold the Black wire over the vinyl harness and tape it again, then tie it with a Nylon tie, tight but without strangling the harness. (electrical tape will dry out and start to come undone eventually, so tie it). Take care in this step, make sure that you SEAL and TIE the unused wire end. By whatever means you seal that old Black wire, keep it isolated from other wires and from the car's Body and make sure it stays sealed permanently. The goal here is to protect the Jaguar's electrical system from any electrical accidents.

1.) The actual Mod to the Front Sidelights wiring begins: Remove about 5/8" of insulation from the end of a new section of 48" long, 18-gauge wire; Twist the copper strands tight and then insert that bare end of the new wire through the 'bullet', allowing it to pass through the bullet's small hole. Then fold the new wire's strands over the side of the bullet, and insert it in the 'barrel' again. Make sure it goes in tight, you might have to squeeze the barrell a bit. Basically, you are replacing the old wire with the new one. Once that is done, let the Sidelight assembly hang again but only over the rubber section of the bumper and away from any metal contact with the fender metal or the bumper chrome. This is very important from now on.
2.) Run the New wire through the large round hole at the fender while wrapping it in a spiral, around and around the outside of the Sidelight Harness as you move it towards the front of the car (following the Sidelight harness), securing it to the harness with Nylon ties every 3 inches or so until you get to the rear of the Headlamp Bucket area; Feed the wire through the rubber grommet located vertically on the side of the Headlamp Bucket assembly, (where other harnesses come and go through towards the FRONT of the car, not up). Use the flat screwdriver to push the new wire through the grommet if too tight; Once the wire goes through, you will need to get your hand in front of the grommet to find and pull the new wire until there's no more wire to pull, but don't pull it too taught, leave a little 'play', that's the reason for having a longer length of wire than it's really needed. You will trim any excess wire later.
3.) Once past the rubber grommet, continue wrapping the new wire down in a spiral around and around the Front Turn Signal Indicator harness, which you became familiar with at the beginning of these instructions when you removed the Front Left Turn Signal Indicator assembly, and left it hanging below the bumper, and which comes up to and through the 'square' grommet below the bumper. Finally, run the wire through the large square rubber 'grommet' located under the front bumper through which the Turn Signal Indicator wire Harness comes out from the body panel, continuing to wrap the wire around and around the harness until you get to the rubber 'boot' behind the Bulb Socket. Don't forget to add nylon ties to secure the wire to the outside of the harness as you spiral it towards the front Turn Signal Indicator bulb socket.
4.) Observe that the Turn Signal Indicator bulb socket Harness has 3 (three) partially exposed color wires connecting to the Bulb Socket: Red, Black, and Green. The Green wire is the Turn Signal/blinker wire You will now cut any excess length of the NEW wire and using one of the Tap Splicers, you will splice the new wire to the partially exposed Green colored wire just before it enters the rubber cover into the Bulb socket Gently 'clamp' the Tap Splicer using the pliers. Tie the wire with a Nylon Tie and you're almost done!

Part 4

Making sure the Sidelight assembly is NOT touching the car's body or the bumper chrome anywhere, (that's why you wrapped it in a towel):
1.) turn the Light Switch to ON; (Switch Position number 1 (Parking lights) will be sufficient): All the four Sidelights and the front and rear Parking Lights should come on as always, nothing different will happen in this step.
2.) turn the Light Switch to OFF
3.) turn the Ignition Switch to Position 2 (Radio) and push the Turn Indicator Stalk switch DOWN for a Left Turn indication: The left Sidelight bulb and the Front Left Turn Indicator bulb should blink simultaneously (in unison). if not, check for a blown Fuse first, (fuse number 3 counting from the Right in the Driver's side Fuse Panel under the steering wheel). Make sure that the Sidelight assembly is not touching any metal from now on, or else you'll blow the Fuse everytime you turn the Ignition Switch to ON. If the fuse did not blow, and still no blinking of the Sidelight, replace the Fuse with one of the new ones anyway, and check the two wiring connections you made, it can't be anything else, except the Bulb in the Sidelight may need to be reset in place from moving the Sidelight assembly around, the bulbs are very sensitive. But if the Left Sidelight is blinking, then smile!

Now turn OFF the Ignition Switch; Turn ON the Emergency Flashers Switch. Both the Left Sidelight and the Left Front Indicator bulbs/lamps should Blink in unison, (but not the other Sidelights because you haven't modified them yet). You are now almost done with the first Sidelight, (otherwise stop and go back to recheck everything). Now turn everything OFF if everything worked ok.

Go back to the Sidelight mounting area at the fender;  EVERYTHING OFF in this following step:
There are two small stud holes and a large round hole at the side of the fender, where the Sidelight assembly mounts through the fender;  Insert and press two of the plastic Anchors through the two small holes, making sure the 'shoulder' of the anchors ends up 'flush' with the painted side of the fender. (you need to get the right size anchors for this to happen, the holes may be a different diameter in your car than mine, the Anchors should fit tight, without movement, otherwise their center hole will be too small for the studs to go through). If the anchors fit tight, using your wire cutters or scissors, cut the excess anchor material from behind the fender BUT leave about 1/16th" inch of the anchor material, in other words, no need to cut the anchors flush with the inner side of the fender. The Wire Cutters come handy here, you can do this 'in situ' without removing the anchors after pressing them in. (the picture shows a red line where you should cut after the Anchor is pushed in place).
Once the plastic anchors are in place, remove the towel from the Sidelight and re-mount the Sidelight assembly to the fender making sure the studs go through the Anchors, (it might be tight at first but they will go through, you can also enlarge the hole with a drill bit if neccesary. (don't use too much force while pushing or you could bend the fender!). Once the studs come through to the rear side of the fender, FIRST insert a Hard Nylon Washer on each stud from the rear, then insert the normal metal washers and hand tighten the nuts in place, ONLY hand tightening the nuts at this point while pressing the Sidelight assembly towards the fender. The excess 1/16th of Anchor material in the rear will be flattened-compressed when you fully tighten the nuts with the socket and ratchet, serving as insulation-isolation. Why isolation ?  you will learn Why if you don't know already:

Turn the Ignition switch ON to Radio Position #2, push the Turn Indicator stalk switch down for a Left Turn Signal, observing that the Bulb is blinking as you start to tighten the Sidelight assembly nuts with the socket and ratchet. If the Bulb goes OFF or stops blinking, the Sidelight assembly is touching metal somewhere and chances are the Fuse blew, so check and replace the Fuse again if needed. Then recheck the Sidelight to see where it may be touching the body. (at the worst case, you might need to enlarge the large round hole to the right of the small stud holes so that the Bulb Hub Ground Lug does not contact any part of the body panel, but that is unlikely, the factory hole is large enough). See Why next:

Part 5

The reason for the plastic anchors at the Front Fenders is that after this wiring Mod and from now on, NO PART of the Sidelight Assemblies should make contact with the car's BODY. The Front Sidelights' metal studs, washers, nuts, and Bulb Hub need to be isolated from touching the fender. The anchors will provide the isolation for the studs. The nylon Washers will provide isolation for the metal Washers and Nuts. The Rubber Gasket behind each Sidelight assembly will prevent the Sidelight body itself from touching the car's body.

Remember that you removed the Ground-Earth-Negative wire 'bullet' coming from the Harness into the Sidelight, replaced it with the New wire, and then spliced the New wire to the HOT-SUN-POSITIVE GREEN WIRE at the Front Turn Signal Indicator, so you end up with a concept called "FLOATING GROUND". Don't ask me what that is, if I knew I would have done it 12 years ago when I bought my 1984 XJ. But Floating Ground WORKS, except that if any part of the Sidelight assembly touches the metal of the fender after the wiring modification, you will blow the Fuse because the Sidelight body is metal and the fender is metal and they will try to ground themselves again, causing a short and blowing the fuse. If the Fuse blows again, you know that some part of the Sidelight body is making contact with the fender's metal, so TEST, TEST, RETEST, make sure the Sidelight body or its parts DO NOT TOUCH any body metal, tighten the Sidelight nuts slowly while watching the blinking bulb at the Sidelight. The two Studs and the Bulb Base Hub go through the fender and even the slightest touch with metal will blow the Fuse. Remember, Modify and TEST ONE Sidelight at a time, don't rush this job.  Fortunately, there is no risk of frying any wiring harness with this Mod. The Fuse will protect the circuit by blowing and shutting down the circuit, isolating it. I have tested this Mod for months before even considering sharing it with you. I am now satisfied it works without any potential risk as long as isolation is achieved.

NOTE: At the Rear sidelights, the Mod is easier as you will discover. Here's what you end up with after modifying both Front and Rear Sidelights: With the Light Switch OFF, (daytime), all four Sidelights will now blink in unison with the Front and Rear blinkers whenever you use the Stalk Switch for a Left or Right Turn Signal. When before they were always OFF during daytime with the Light Switch OFF, now they will blink on and off with your normal blinkers. This means that other drivers can now see your intentions from the side of your Jaguar, but they couldn't before unless they were in front or behind your car.

The Emergency Flashers and the Sidelights will blink in the same way, in unison during the day, (Light Switch OFF), this means that you will have 8 Emergency Flashing bulbs when you use the Emergency Flashers. (when you only had 4 before). This means that in rain or fog or snow or emergency, your intentions WILL BE SEEN from every angle when you use the Emergency Flashers or the Turn Signals.

With the Light Switch ON, (nightime or during the day if you wish), this Mod gets even nicer:  The Sidelights or the Emergency Flashers will now blink intermittently with the normal Turn Signals as long as the Light Switch is ON; That means that when the original Turn Signal Indicator Bulbs are on, (at the Front and Rear), the Sidelight Indicator Bulb is off, and viceversa. The Blinking speed is not changed.  AND, when you turn the blinkers, (Turn Signal Indicators) or the Emergency Flashers to OFF,  but the Light Switch is ON, the Sidelights come back ON and stay ON continuously as they did before. Nice ehh? Works in every logical way. What more could anyone ask for? It works without any compromise! It also looks very cool when the lights are blinking intermittently at night, very high Tech! Even better still, the Bulb Failure Module Sensor continues to work normally. Nice, nice, very nice.

(c) 2004 J. A. Maymon

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