Hi guys. I wonder if anyone can help. I have a 2007 FL2 XS - with upgraded 'PowerfulUK' LED Rear light clusters - which have all been working fine for over 3yrs.

Recently a problem seems to have developed whereby the N/S Tail light can be working one minute, then not working the next. It's not the LED lamp cluster its self.....Because as I say if I turn the lights ON, sometimes stays illuminated for abit....but by the time I arrive somewhere and check if its still on....its OFF. It also turns on/off from the keyfob? So really frustrating.....but would like to get sorted now darker nights drawing in.
I have read on www about them all being controlled by a CEM, and have tried the CEM 'Reset' procedure that others have posted on Youtube - but intermittent problem still present
Any ideas folks? Current Vehicles:
2007 Freelander 2 - XS Tabora Flame TD4
1989 Range-Rover Vogue SE V8 3.9 Petrol/LPG
1976 Land-Rover SIII SWB 88 County, 2.25l Petrol/LPG
Past vehicles:
1999 Range-Rover P38 V8 4.0 - Money pit
1988 Range-Rover V8 3.9

Intermittent problems are never fun to diagnose. Pretty old school, but I wonder if it's a problem with the connector? I'd be tempted to pull the unit out and inspect the connector and all the contacts inside it for loose fit or corrosion. Treat it with some de-oxit or similar connector cleaner, a bit of silicone spray and re-assemble.
While it's in bits, measure the voltage coming to the unit while the car is running, and see if it is earthed properly. Sounds like you have a good one on the other side for reference, so that's handy.

Hi BalticBlue,
Thanks for your reply. The multi-pole connector all looks pretty good, clean, and secure fitting. All the other lights with the Lamp unit are working fine (indicators, Stop lights etc) just the Tail Light that seems to have a mind of its own.
Just I random thought I had....About 10mths ago I fitted a towbar - and as part of the electrics for that I had to fit a small plug in module for the trailer lights - this being located within the boot floor space on the N/S. Could this have anything to do with it? Probably not....I'm just clutching at straws  Current Vehicles:
2007 Freelander 2 - XS Tabora Flame TD4
1989 Range-Rover Vogue SE V8 3.9 Petrol/LPG
1976 Land-Rover SIII SWB 88 County, 2.25l Petrol/LPG
Past vehicles:
1999 Range-Rover P38 V8 4.0 - Money pit
1988 Range-Rover V8 3.9

If I understand correctly, indicators and other lights are working, and there is one particular section of taillight that does not work. If that is the case, I would advise you to find out which of the pins in the connector provide 12v to the particular section of taillight and check with multimeter if there is 12v feed provided. If there is, then there is a problem within the headlight itself. If there is not, or the voltage is intermittent, I would definitely dismantle the plugs, clean them, bend the metal connectors within them a little. If that doesn't solve the issue, you should just go along the particular wire and check where the problem lays.

Hi Blaster1232
Thanks for your reply.
Yes, all other lights within the N/S lamp unit work fine. Its just a problem with the Tail light intermittenly working or not. Its so frustrating

Oddly, if you press the 'lights' button on the keyfob the tail light works (so its not the LED light its self), and will even come on for while when lights selected off the dash switch.

It's as if something (like a blip in the CEM/ECU happens subsequently?) - or do you think it is just a bad connection? Current Vehicles:
2007 Freelander 2 - XS Tabora Flame TD4
1989 Range-Rover Vogue SE V8 3.9 Petrol/LPG
1976 Land-Rover SIII SWB 88 County, 2.25l Petrol/LPG
Past vehicles:
1999 Range-Rover P38 V8 4.0 - Money pit
1988 Range-Rover V8 3.9

Clutching at straws as you say have you tried a hard reset on the battery

Each Lamp Cct on the FL" is controlled and protected by separate FETs in the CJB.

If a short or other fault is detected, then power will be removed from the lamp circuit. (I think until car is shut down/locked)

It looks as if here are some general DTCs for lighting if it is being shut down.

The downloadable Repair Manual and Wiring diagrams may help

https://www.freel2.com/forum/topic10621.html FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

I Like Chips wrote:

Clutching at straws as you say have you tried a hard reset on the battery

IanMetro wrote:

Each Lamp Cct on the FL" is controlled and protected by separate FETs in the CJB.
If a short or other fault is detected, then power will be removed from the lamp circuit. (I think until car is shut down/locked)
It looks as if here are some general DTCs for lighting if it is being shut down.
The downloadable Repair Manual and Wiring diagrams may help
https://www.freel2.com/forum/topic10621.html

Hi Ian
Thanks for your reply.
Those links to the various manuals are very useful. I will download them and study.

Yes, I had read about each and every lamp being controlled by it's own FET transistor. But if the FET was shorted/ or open circuit, why would it work sometimes?

Tonight for example I drove home from work - approx 30mins journey, and when I got home I purposely got out to have a look before shutting the vehicle off.....expecting the N/S to be OFF...and both Tail lights ON. So Its really got me puzzled

I have got an OBD2 DTC reader - but having hooked that up, only seems to interrogate the Engine & emissions ECUs/CPUs - not anything relating to lighting/ body control.

Any other ideas? Just want to get it reliable before the dark nights drawing in etc. Current Vehicles:
2007 Freelander 2 - XS Tabora Flame TD4
1989 Range-Rover Vogue SE V8 3.9 Petrol/LPG
1976 Land-Rover SIII SWB 88 County, 2.25l Petrol/LPG
Past vehicles:
1999 Range-Rover P38 V8 4.0 - Money pit
1988 Range-Rover V8 3.9

In the Exterior Lighting Wiring Diagrams towards the end of the Downloadable Repair Manual you can see the FETs on page 2of4.

They are software controlled by the CJB. I cannot find a written description of the workings of the logic, but the only fault codes for these lamps appear to be 'Open' or 'Short' CCT, so they most likely just monitor the current levels feeding these lamps.

As these are upgraded LEDs it may be that they are internally failing to give the indication of the right levels back to the SJB although still working. (These units will have some internal circuitry to provide the right load/feedback to the CJB)

I am sure that fully locking the vehicle should reset most electronics on the FL2.

Without being able to confirm the error codes, you may have to exchange the suspect lamp unit for a new one.

The side lamp wire is Violet/Green on pin 2.

C1126-11 Position Lamps General
Electrical Failures Circuit - short to ground
Position lamp circuit - short to ground
Refer to electrical circuit diagrams and check position lamp circuit for short to ground

C1126-12 Position Lamps General
Electrical Failures Circuit - short to battery
Position lamp circuit - short to power
Refer to electrical circuit diagrams and check position lamp circuit for short to power

(I hope someone has a test procedure they can suggest for the suspect lamp unit.) FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

My comment will not actually help your situation, but in Sydney I have never in my many previous lives seen so many cars, or more to the point new cars, with 1 or more front & OR rear lights failed, & also brake lights, 1, 2 or even all three.

If safe to do so at a set of stopped traffic lights I let them know. In general the answer... 'Oh really', why does one bother!

Seems to be a modern problem, both LED & attitude.

Maybe swap out LEDs for failsafe incandescent. In 45 years of driving I have never had a failed incandescent globe. Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18

Would a 2007 model have been fitted with LED bulbs? MY 09 GS manual in Lago Grey, Wood Co arm rest and side bumper strips - now sold.

MY 15 SD4 SE Auto Orkney Grey with colour coded Bumper Door Mouldings

No, just incandescents. CANBUS compatible leds could be used but none were fitted as standard.

notwen wrote:

Hi guys. I wonder if anyone can help. I have a 2007 FL2 XS - with upgraded 'PowerfulUK' LED Rear light clusters - which have all been working fine for over 3yrs.

Recently a problem seems to have developed whereby the N/S Tail light can be working one minute, then not working the next. It's not the LED lamp cluster its self.....Because as I say if I turn the lights ON, sometimes stays illuminated for abit....but by the time I arrive somewhere and check if its still on....its OFF. It also turns on/off from the keyfob? So really frustrating.....but would like to get sorted now darker nights drawing in.
I have read on www about them all being controlled by a CEM, and have tried the CEM 'Reset' procedure that others have posted on Youtube - but intermittent problem still present
Any ideas folks?

notwen wrote:

Hi Blaster1232
Thanks for your reply.
Yes, all other lights within the N/S lamp unit work fine. Its just a problem with the Tail light intermittenly working or not. Its so frustrating

Oddly, if you press the 'lights' button on the keyfob the tail light works (so its not the LED light its self), and will even come on for while when lights selected off the dash switch.

It's as if something (like a blip in the CEM/ECU happens subsequently?) - or do you think it is just a bad connection?