[bobv]

I have a 2004 Discovery II. With the turn signal switch in the neutral (off) position, when I first start the car the left turn signal turn on. They remain on for several minutes then shut off. At this point, switching on the left turn signal does not work. At anytime I can activate the right turn signals and they operate normally. At random times, the left turn signal will just turn on. I tried swapping the relays in the passenger compartment fuse box, no change. Replaced the turn signal switch, no change. Could I have a bad BCU?

 

[bobv]

Forgot to mention a few other items. All the lights do work and hazards appear to function properly. Not sure if these are related: 1. the wireless key entry does not work 2. Sunroof on occasion will open, not fully just back pops up, when I shut off engine.

 

[sierrafery]

Could I have a bad BCU?

Yes, or faulty fusebox unless you are unlicky enough to be a wiring issue which can be a nightmare

 

[bobv]

Fery, Thank you. Is going to a LR dealership the only option to fix\replace a BCU?

 

[masantschi]

The Fuse Box that Fery is referring to is in the passenger compartment, on the driver's side. They are prone to failure over the years and it's just not worth it to get it fixed. Symptoms are random electrical glitches, like you are experiencing. Mine caused random failures in with my blower and my turn signals/steering wheel controls. You can find them fairly readily in used condition on ebay. It's a 30-min job to swap it out.

 

[bobv]

Masantschi, thank you. Will try swapping out the fuse box.

 

[sierrafery]

Be aware, you need a fusebox removed from a facelift cos they are not the same with pre-facelift fuseboxes, it's almost plug and play, you have to disconnect the battery negative lead before the swap then after reconnection turn ignition on 2 and let it so 5 minutes for remobilisation dont do anything else untill then. For the BCU you need a D2 compatible diagnostic tool, the cheapest you can find which can program it is Foxwell NT530 unlocked for JLR to make the engine ECU learn the new security code and set the BCU for the equipment of your vehicle(air suspension or coils, gearbox type, ACE or not, synk the fobs, etc)

 

[masantschi]

Bobv - since you are new, by facelift model, Fery means 2003 & 2004, specifically. That's when the 99-04 got the facelift.

 

[sierrafery]

I made some research and it seems that a cheaper tool appeared on the market but i have no ideea if it can program the BCU or not AUTOPHIX 7310 All Systems Car Diagnostic For Land Rover Code Reader OBD2 Scanner | eBay

 

[bobv]

Thank you guys. I did order a replacement fuse box (2003-2004). Will let you know if it works. I do have a Autel ODB2 reader, just got it last week but think I need the VCI to program ECUs.

Glad to be a new member here. I have a 2000 D2 which I build up for off-road; 4" OME lift, TF 8 stage shocks, ARB locking diffs, etc etc. Last year, we were rescuing a disabled jeep and ended up tweaking my frame. Doors wouldn't quite open with rock sliders on. Long story short, found a used 2004 and swapping out all my upgraded parts. It is in fairly good shape but few issues I am working through, as mentioned above.