Jaguar XJ6 Series 3 Turn Signals, Indicators Not Working
On the Series 3 the indicator feed passes through the hazard switch even in normal use, so dead indicators with working hazards usually mean dirty hazard-switch contacts or a bad fuse 10 clip, not the flasher. One dead lamp with a good bulb points at the bulkhead connector or the lamp earth. I'd start by noting whether the hazards still work.
How bad is it · Garage, carefully
Use hand signals and get it fixed before driving far
The engine isn't affected, but other drivers get no warning when you turn.
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.
Dirty or cracked hazard switch contacts
The flasher is fed through the hazard switch in both modes: from fuse 10 for the indicators, from fuse 2 for the hazards. Contacts that have oxidised from disuse, or a switch body cracked by age, cut the indicator feed while the hazards may still work, fully or on one side. Inside, a small white plastic carrier with a copper contact breaks, and the offset pegs on the lever crack; fore-and-aft play in the lever is the first sign.
No indicators and no ticking, while the hazards work or flash on one side only; pressing on the switch brings them back for a moment. With the hazards on, one side may flash only until the stalk is moved, because the dash arrow earths through the dark lamps.
Look for 12 V on the light green/pink wire at the flasher with the stalk set to left or right, while you work the hazard switch.
Run the hazards for two or three minutes, or work the switch briskly many times; contact cleaner helps, with the column shrouds off. A broken switch is replaced: three screws from below, angled down with the lever up. The pivots are thin and brittle, and a new switch may need its bracket opening enlarged. Before taking the shrouds off, slacken the two bolts under the column so it drops a little; forcing the cover breaks the switch.
Fuse 10 not making contact in its clips
Fuse 10 (15 A) feeds the indicators with the ignition on; fuse 2 (15 A) feeds the hazards. A fuse that tests good can still pass nothing when a clip is missing, bent away or corroded, or the end caps are corroded.
Indicators dead and silent, hazards fine; the fuse itself shows continuity.
With the ignition on, test for 12 V on both sides of fuse 10 in place, at the clips, not just across the fuse out of the box.
Clean the clips and bend them back so they grip the fuse; replace any glass fuse that only looks good.
A bad contact in the bulkhead connector to one front lamp
Each front indicator is fed through a white rubber multi-pin plug on the bulkhead, engine side. On the right side this is CF3, carrying the green/white feed, and a corroded pin there kills that lamp and its dash arrow.
One front indicator and its dash arrow dead, the rear on that side working; a good bulb and a good earth; no power at the socket when the indicator is on.
Open the connector and look for the feed on the switch side, then meter through to the lamp side. Power in and a good wire out means the contact inside the plug.
Pull the connector bundle out of the bulkhead channel, unplug and replug it, and clean both terminals and the connector body.
The flasher unit DAC1731, or a wrong replacement
The flasher is a 4-pin Hella unit, Jaguar DAC1731, under the left of the dash. An internal short can make both dash arrows light solid and flash crossed. Generic 5-pin flashers don't suit; the unit needs pins 49, 49a, C and 31, as on the Hella TBB44, Lucas SFB191 or Rover PRC8864. Inside are discrete parts on a small board: cracked solder joints and a tired 4.7 µF timing capacitor make it work intermittently, and a plain parts-store 4-pin relay is no substitute at all.
Both green arrows on as soon as the ignition is on, or flashing the wrong way round; or nothing at all after fitting an aftermarket flasher. An ageing unit often shows first as indicators slowing until the dash arrow sticks on, or a dash arrow that blinks a few times and stops while the outside lamps keep going.
Check pins C and 41 of the old unit for a short, then try a known-good unit of the right pattern.
Fit a correct DAC1731-pattern flasher. If the dash arrows still both light, test the diode in each arrow's feed. A failing original can be repaired on the bench: release the case, resolder the four main pins at the base of the board and fit a new capacitor of at least 63 V; a larger value slows the flash rate.
A replacement hazard switch wired wrongly
Replacement hazard switches carry different terminal markings, and the indicator and hazard circuits are intertwined there. One swapped pair is enough to kill both, or to give indicators only with the ignition off.
Indicators and hazards dead, or odd, straight after a switch was changed. Swapping brown/orange with dark green gives indicators only with the ignition off and hazards only with it on.
In hazard mode the switch joins green/white and green/red to light green/blue, and brown/orange to light green/pink. Bridge those at the plug to simulate hazard, and test with a test lamp, not only a meter.
Rewire the switch by function against the wiring diagram, not by terminal position. A layout proved on one replacement switch: terminal 1 takes light green/blue; 2, dark green/white; 3, light green/red; 4, dark green/light green; 5 stays empty; 6, light green/pink; 7, dark green; 8, brown/orange.
Burnt blocking diodes in the dash arrow feed
Both dash arrows are fed together from the flasher's C terminal and earth through the dark side's outside lamps. A blocking diode in each feed, a bulge in the wire behind the instruments, keeps the two arrows apart; when one burns open the arrow goes dead, and when one shorts the arrows glow together or flash crossed.
Outside lamps flash correctly, but a dash arrow is dead, glows dimly with the ignition on, or flashes on the wrong side; the bulb holder shows only a fraction of a volt.
Unplug the light green/brown wire at the flasher and meter each diode both ways: near zero one way and open the other is good, open or shorted both ways is failed. A bypass with needle probes proves it without cutting.
Replace the failed diode with a 1N4006 or 1N5402. Don't simply leave both out: without them the two dash arrows fight each other.
LED indicator bulbs: the flasher reads them as a failed lamp
The DAC1731 senses lamp current, and the dash arrows earth through the dark side's bulbs. LEDs draw too little, so the unit treats the load as a failed bulb, drops the dash arrows, and the arrows lose their earth path.
Straight after fitting LED indicator lamps: outside lamps flash, often too fast, and the dash arrows stay dark.
Refit ordinary filament bulbs all round, or at least at the front, and see whether the dash arrows return.
Keep filament bulbs in the indicator lamps. With LEDs throughout, a load resistor from the flasher output to earth, or a 4-pin electronic flasher with one jumper added to feed the C terminal, brings the arrows back; such a unit gives no bulb-failure warning.
Dirty contacts in the indicator stalk
The stalk switch routes the flasher output to the left or right lamps. Its contacts tarnish like the hazard switch's, and the indicators become erratic rather than dead.
Indicators that work sometimes, flash irregularly or drop out in one direction, with the hazards normal.
With the column shroud off, work the stalk through both positions while watching the lamps.
Spray electrical contact cleaner into the stalk switch and work it many times.
A corroded earth or bulb socket at the lamp
The front indicator connections take water and salt. A corroded earth wire or socket side contact stops the bulb lighting even with a good feed.
One indicator dark or dim while its sidelight works.
Bridge the bulb holder body to a known-good earth with a jumper. Scratch the centre contact clean, put a test lamp on it and an earth, and look for the flash with the indicator on. Find the flasher earth wires too: they run in a bundle in each wing, and cleaning them can cure a weak, slow flash.
Worth trying: clean the socket and run a new earth wire back to the body.
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.
Do the hazards work?
Hazards working, indicators dead: hazard switch or fuse 10. Both dead: flasher or its common feed. One corner dead: that lamp's connector or earth.
freeExercise the hazard switch
Run the hazards for a few minutes, then try the indicators again.
freeTest fuse 10 in its clips
Ignition on, 12 V on both sides of the fuse in place; then fuse 2 for the hazards.
a test lampFollow the feed to the flasher
Light green/pink at the flasher; with the flasher out, bridging light green/pink to light green/blue feeds the stalk directly.
freeDash arrows wrong, outside lamps right
Filament bulbs everywhere first, then the blocking diodes behind the instruments, then the flasher.
a meterOne lamp dead: bulkhead connector and earth
Clean the multi-pin plug on the bulkhead and the lamp earth.
freeFit a correct flasher
A DAC1731-pattern 4-pin unit, not a generic 5-pin one or a plain relay; a failing original can be resoldered.
a flasherThe 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, 1987 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
- XJ6 Series 3 fuse boxesWhere fuses 2 and 10 sit in the main panel of the 1987 layout.
- Jaguar XJ6 Series 3 Battery Drain, Flat After a WeekIf several circuits play up together on a car that has stood.
- Jaguar XJ6 Series 3 Central Locking Not WorkingAnother circuit that shares the main fuse panel's tired clips.
- 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.