Indicator / Sidelight problem on 2008 Tekna

[thetcutkid]

Hi,

I know there have been several posts from QQ owners with early models about issues with indicators and brake/side lights flashing together, often whilst under braking. In that regard, I’m no different , however, I would appreciate a little advice to try and avoid a trip to the garage if at all possible, although I dare say the overriding response will probably be ‘take it to the garage’ !

I have a 2008 Tekna, 2.0 Petrol, 4WD which I’ve owned since 2014.

2 months ago I first noticed that when indicating left, if I put my foot on the brake, I would hear the rapid ‘tick, tick’ of the indicator which, under normal circumstances, would indicate a blown bulb. If I didn’t touch the brake, the indicator would ‘tick’ normally.

With the car on the drive and the left indicator working, I went round the car and found that the rear indicator and brake or side light (I actually think it’s the side light) were flashing together, albeit with reduced brightness. I then got someone to press the brake pedal and, as I write this, I cannot remember whether that changed anything visually outside, it was either they continued to flash together, or the indicator didn’t flash at all.

So I take the lens off and disconnect the 4 pin connector from the bulb holder and since the plastic on the end of the connector is bright yellow, it was immediately obvious that the plastic around one of the female pins was black and very slightly melted – looking at the corresponding male pin on the bulb holder, that too was discoloured, whereas the other 3 pins were still a shiny silver colour.

I took this as a positive inasmuch as there had obviously been a problem with that pin which I assumed was the cause of the weird light behaviour and ordered a new one. I also ordered a new bulb holder but had a heck of a job trying to find one - I couldn't find anywhere in the UK that had one (even listed as out of stock !), it didn’t appear on Nissan’s available parts list for my model of QQ and I ended up having to order it from China via Amazon.

About 6 weeks later it arrived from China and I set about installing the new parts.

Taking care to photograph how the old one was wired up, I cut off the 4 pin connector, stripped back to fresh wire and reattached the new connector, swapped the old bulbs across onto the new bulb holder and put everything back together and…

…nothing had changed, with the left indicator working, both indicator and brake/side light flashed together and if you put your foot on the brake, you got the rapid ‘tick’, ‘tick’ sound of the indicator.

Slightly crest fallen, I took everything apart, half expecting to see another blacked pin on the connector but it’s perfect, there’s no evidence on either the connector or the bulb holder of any blackening or melting.

That’s how things have been for a week or so until two days ago…over the weekend I noticed that with the left indicator working, regardless of whether your foot is on the brake, the indicator now ‘ticks’ rapidly and on checking round the back of the car, neither the indicator or side light are flashing.

I can’t get the left indicator or side light bulb to come on at all, regardless of whether the brake pedal is pressed – the sidelight bulb won’t light even if I turn the sidelights on from the steering wheel stalk.

The brake light works in any scenario, with or without the indicator on, with or without the sidelights on.

With the indicator and side light bulb both not working, I did wonder about a blown fuse but the only reference I can find to lighting on the fuse box diagram is ‘Stop Lamp’ and that fuse is ok.

As a matter of interest, what fuse descriptions relate to the various external lights ?

The filaments on both bulbs are intact, so I don’t believe this is a bulb issue.

So anyway, have I really exhausted all options, is a garage my only choice now or is there anything else I could check ?

Many thanks for your time and if you’re still reading, many apologises for such a long first post!

Nick

[calnorth]

Path of least resistance problem in an earth fault situation.

What you describe is a circuit that has a bad earth and gets to earth via a different route through adjacent circuits. Often seen in older cars. Hall mark being the adjacent circuit(s) bulbs dimly lit. Dimly lit because the bulbs concerned also present their resistance on the path to their earth. Resistors in series.

From J10 Diagnostic diagrams:
Body Control Module (BCM) controls internal/some external lights.
Left and Right signalling are in distinct groups electrically...Left Turn is 3 lamps Front, Side and Rear so is Right Turn (each include Hazards flash function)

Fog Lamp is electrically separate from BCM
Brake (Stop) Lights are electrically separate from BCM

Tail/Parking/No Plate are direct from IPDM (Power Dist Module)

The above design shows distinct circuit isolation.
Most of the lamps are physically clustered though and probably share the same earth point..earth wiring is numbered separately or not at all

The first place to look was always the cluster bulb holders and related local wiring...you appear to have done that.

Try taking an earth wire (-ve) direct from the battery around to a rear cluster. Place it on a turn bulb earth pin..select turn
You might do that systematically...disconnect other cluster completely.

I'm not sure if the car has a transmitted earth system across the body parts somehow...wired earth front to back. IPDM is main power distribution around the car so maybe passing earth along with signalling etc. An increased resistance somehow to earth can cause adjacent path to be used...hence your problem.

In the severest case that an earth is supplying high resistance further back along a wiring loom, that does need close inspection of related plugs/sockets. Not wishing to go on a wild goose chase there of course..

Afternote:

I'm just trying to work this out (below) from what I said about circuit isolation - above:

"…nothing had changed, with the left indicator working, both indicator and brake/side light flashed together and if you put your foot on the brake, you got the rapid ‘tick’, ‘tick’ sound of the indicator".

Regarding Afternote:

TURN SIGNAL LAMP CIRCUIT (diagnostics)
Description
BCM performs the high flasher operation (fail-safe) if any bulb or harness of the turn signal lamp circuit is open.
NOTE:
The turn signal lamp blinks at normal speed when using the hazard warning lamp.

Turn selected + Brake pedal pressed
I suspect that because the turn circuit is using a path to earth via the Brake bulb and can I assume that it fully illuminates? If it does fully illuminate then the bulb will get hot and increase resistance. That higher resistance could represent an open circuit bulb to the turn controller (in BCM) which triggers high flasher operation (fail-safe) condition above....maybe?

[thetcutkid]

Hi calnorth,

Many thanks for taking the time to post such a detailed reply.

I must apologise as I am a complete layman in terms of car electronics, so some of what you have posted has gone over my head a bit

Under your heading 'from J10 diagnostic diagrams' I assume you're talking about the fuse box layout as I can see two BCM fuses identified on the grid diagram on my fuse box cover? Where you mention IPDM, is that related to the fuses located in the engine bay ?

Regarding running a earth wire from the negative terminal on the battery :-

1) what will this prove/disprove in terms of the fault ?
2) what sort of diameter wire would I need to do this safely ?
3) I appreciate there are only two pins on the bulb itself but how do I identify which is earth ?

Nick

[calnorth]

ok...if you are not experienced with electrics I'd say leave this problem to a car electrician. What I had proposed could be damaging to the vehicle if not handled competently.

Diagnostics is the test procedure to determine the cause of a fault.