I was pulled over the other night because my rear lights were out. Not just a bulb but all the rear lights. Brakes lights and flashers worked but no taillights.

The following morning I went to check and they all worked. I pulled a bulb and the bulb integrity light came on as normal but it did not indicate an issue when I was stopped.

A few days ago a co-worker pulled in behind me and said the same thing no taillights but when I check the lights, I had already turned off the car they were working.

This AM the same thing happened and I had gotten in the habit of checking them when I leave. They were on when I left the house but about 30 min later when I stopped at work I had no exterior lighting EXCEPT the headlights.

The dash lighting and the interior lighting was all fine and there was no indication of a failure via the bulb integrity system.

I was thinking the switch but I haven't had a chance to look at the schematics and see where a possible failure might be but thought I would toss this out to see if anyone has had or seen this issue in the past.

Thanks ahead and when I figure it out Ill post up.


I just found this..

https://www.jaguarforums.com/forum/x...m-fixed-28813/

so its a place to start

 

Hi Jeh,

I haven't checked the schematics either, but I do know that each tail lamp assembly has its own Bulb Failure Module (BFM) and ground point, so your problem must be upstream of both BFMs since all the tail lamps are out. I think I recall that the lamp assemblies are controlled by relays inside the BFMs, which are in turn powered by a main relay somewhere upstream. Perhaps that relay is failing or its socket is corroded. I believe the brake lamps are controlled by a separate relay, so they can work independently of the tail lamps.

Please let us know what you find.

Cheers,

Don

 

Hi Don

I am looking at the schematic (what a disaster BTW) and from the other post it seems as if the front and rear lights are on different circuits and not controlled by the same relay.

If this is the case this leads me back to the switch. I was staring at the schematic looking for "the switch" then discovered why I couldn't find it... I was looking for a switch not this..





Still working at it....


So after staring at the schematic for a while the only common denominator is the headlight switch or the H module relay. Since it seems to be a "time" issue as the lights need to be on a while Im thinking its probably the relay. Ill check it in the AM by trying to give it a "whack" in the general area and see if they come back on.

At 5:30 in the morning thats about as much science as im going to get.

 

I pulled out the H module relay and took it apart. I found 9 bad solder joints with a few more that looked suspect so I just resolderd the whole thing and popped it back together.

I will take a few pictures before I buttons it back up and update this.

 

This seems to have fixed it. All it took was a little solder on the joints and in most of them it was just a matter f heating it up and letting it reflow.

The relay in question is the one on the left.



Here are a few shots of the opened relay. I just hit all the joints. It was literally a15 min fix.





A few don't look so hot as my arthritis causes some shaking but so far no issues.