Electrical issue : turn signals disable headlights
 

Hi all,

I've got this weird issue since some time, which I can't identify -- I've read the many threads about the turn indicators problems but mine seems to be different.

Initially, I've just noticed the sound stopped being emitted from the steering column speaker, but planned to look into it later as the indicators worked anyway. Yesterday, the headlights were on "auto" and it was rather dark, so on. I realized that each time I would activate one of the turn indicators, the headlights would go off.. then on again when turn indicator disabled.

I've checked or tested each and every relay and fuse in the car (needless to say, I'm hating Jaguar engineers' guts right now), and they are all ok. I've disconnected the battery for a long while, but it didn't change anything.

Actually, kinda : the left turn signal now makes the headlight blink -- off then back on --, while the right one shuts it down until deactivated. The corresponding relay in the main fusebox from the engine bay makes an audible click sound when the headlights go on or off. I couldn't find a relay about the turn indicators.

I've checked the speaker and there is a voltage going through it, so I'm guessing it's fine. Not sure how I can easily get a test sound out of it though.

Ground connections seem to be ok, although there's a shitload of those so I possibly missed one that would be broken.

Electricity not being my strong suit (and yeah, I'm still searching what my strong suit is exactly), I don't quite know where to go from here. Does this ring a bell to any of you Jag veterans? :-)



Last thing, no connection but I'm still pissed about it ; an O2 sensor is fried (lucky me, the upstream right one, easiest to reach -- unlucky me, it's competely stuck and I'll need to remove the whole catalyst to hopefully unscrew it). The car has 122k km (about 76k miles I think), and I bought it at 107k km. O2 sensors shouldn't fail so soon... this pretty much confirms my suspicion that the mileage was tampered with (the rest of the car is in poor shape, worn off, such as the suspensions and silent blocks, gearbox was obviously replaced -yellow markings on it- but no invoice about that). End rant :p

Your multi-function switch (turn signals/headlights) has a broken solder joint or two. You need to take off the steering wheel and the plastic around the steering column. Then you need to either replace the switch (expensive), have somebody else replace it (probably much more expensive), or resolder whatever came loose. I did the latter when this was happening to me. Maybe you have a friend who can solder?

The reason it is flashing your headlight when you turn on the turn signal (or a variety of other weird things it could do) is because the wire that has become desoldered is loose and is touching other contacts, sending a signal to the other things controlled by the same switch.

Hi Bill,

I hadn't thought of this possibility, I'll look into it (and yes, I can solder myself, hopefully the loose cable will no be too deep into the steering column..)

Thanks for the heads-up !

It should be at the base of the switch itself. I don't remember if you have to open up the switch, but you definitely need to remove it.

Bill,

You were spot on... I removed the steering wheel and got access to the switch ; one of the cables was unsoldered. I soldered it back and the turn signals no longer disable the automatic headlights.
There is still no sound however, although there is power going to the speaker, which I assume is fried (although I can see nothing wrong on it, but well).

Until I can grab a replacement speaker, I attached an LED on the speaker's cable, and taped it above the speedometer... definitely ugly, but at least it flashes when sound should be coming from the speaker, so I'm not going to drive with a turn signal on or forget about the headlights when exiting the car.

Cheers