'87 S3 turn signals not working

(Ron Knipper) #21

Every time I look at the JL forum, the XJ flasher issue reoccurs. While the Charlie Nowlin FAQ is correct, it doesn’t directly address the flasher replacement/interchange issue directly.

I believe Doug is on the right track; it sound like the 5-pin replacement flasher is just the wrong part. When I did my 86 XJ6s3 LED upgrade a few years ago, I researched the flasher issue extensively.

  • Only a handful of aftermarket 4-pin flashers are compatible with the XJs3 using incandescent bulbs.
  • I didn’t find any aftermarket compatible flashers that worked correctly with LEDs, so I built one (a completely separate topic).
  • I didn’t find any compatible 5-pin flashers.

The vast majority of 4/5-pin aftermarket flashers are designed for 2 indicator circuits (eg front circuit plus rear circuit). Those will not work. You need:

  • pin 49 = power from hazard switch.
  • pin 49a = stalk and lamps.
  • pin C = pilot circuit for dash indicators. This is different than a 2nd circuit; there is no bulb fault detection on a pilot circuit. On the DAC1731/TBB44. the pilot circuit signals bulb failure while the remaining exterior lamps flash normally.
  • pin 31 = ground.

Compatible flashers include Hella TBB44 (perhaps some NOS available), Lucas SFB191, Rover PRC8864, and a few others.


(Roger Coole) #22


In case you missed it, I was on the wrong end. My bad. My
flasher is a Hella TBB44.

The hazard portion of the system works normally. That makes me
believe the flasher is ok, as well as that portion of the wiring.
I’m going to compare my wiring with this next. Maybe I’ll locate
the problem. At least I hope to.



(Frank Andersen) #23

The main difference between the ‘hazard’ and ‘indicator’ mode is the power feed through the hazard switch, Roger…

Ie, the relay connections are the same in both modes - the hazard switch, apart from switching power feed, just bypasses the direction indicator switch. Are you sure that there is power on light green/pink (49) in both ‘hazard’ and ‘indicator’ position?

I know you have checked, at the fuse #10, that power is going through the fuse, but does it reach relay 49?. And have you tried jumpwiring 12V directly to relay 49 - to see if the indicators the work?

Basically, the relay works by power to 49, the operates as 49A is grounded through the bulbs in ‘hazard’ - and through relay C in indicator mode. The latter two represents the relay coil, powered in the respective positions, with 31 as the relay coil ground. Internal resistors(?) balance the different resistances to give the same blink rate in both modes.

However, the relay numbers may differ from the original diagram, but the principle is the same.

In brief; given power as described; if one mode works, so should the other. However, apart from correct connections; any wiring diagram requires the indicated wires, by colour code, is at least present…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

(Roger Coole) #24

I’m losing power between fuse 10 and the harness connector. I’ll
have to find a tap for Ignition Feed and add an inline fuse holder just
to be safe.

Thanks for all your help, everyone.



(Roger Coole) #25

Closer inspection revealed that one of the upper fuse clips was missing and the other side was not making contact with the fuse. After careful bending of the remaining half clip, it all works as it should. Now just have to put it all back together.

Thought you’d all like to know.


(Frank Andersen) #26

Solutions should be integral to presenting a problem, Roger - very welcome…:slight_smile:

xj6 85 Sov Europe (UK/NZ)