Nissan Micra K12 offside tail lamp and number plate lamp

Niece presented my with her Micra this weekend. Said she kept getting flashed at from behind and could I check the tyres. They were OK so further questions were asked. MOT tester had let non working offside tail lamp and number plate lamp slide with "you need an auto electrician".

Inspection shows no power to them. Some one has butchered the number plate lamp connector. There is blue insulation tape on earth splice but it's OK. The foam seal is missing from the tail lamp. Shorting the tail lamp to the indicator on loom plug makes the number plate lamp flash so wherever it's splice is to the cluster loom it's OK.

Offside, nearside and number plate all have different colour feed wires.

I'm sure I've seen others with same issue. So where does the offside tail lamp wire break?

Reply to
Peter Hill
Loading thread data ...

Obvious first question - have you checked the fuse?

A randomly-selected K12 on Autodata shows it as F35(10A) in the engine bay fuse box.

Chris

Reply to
Chris Whelan

I hope you reported him. That doesn't come into the advisory section. And it's obvious your niece continued to use the car at night in this condition.

Reply to
Dave Plowman (News)

Are the offside tail and number plate lamps on a separate fuse to the nearside? As nearside tail lamp works, as do the front side lamps.

Reply to
Peter Hill
[...]

Yep. As are all vehicles made since Adam was a lad.

A blown fuse would otherwise leave a vehicle with no rear lights at all. The same rule applies to headlights.

Chris

Reply to
Chris Whelan

The Micra has a well known problem with wires breaking in the hatchback (boot) lid. The wires are just that little bit too short. Open boot and you will see a shielded wire loom on the right hand side Peel or cut back the black tape and look for a broken wire. I've been there :-( It's dead easy to fix. As for the missing foam seal ------------- dunno.

Reply to
Mr Pounder Esquire

Care to speculate when fusing of any sort first came in for lights?

Plenty other faults could result in no rear lights at all. It could mean quite a bit of extra wiring etc to fuse them individually. Unless the car is already wired for German style parking lights.

I'd be surprised if every cheap car like a Micra had individual fusing everywhere.

Reply to
Dave Plowman (News)

Not speculation, but many cars of the Sixties had two fuses; one for ignition-switched circuits, the other for things that remained on. Lighting generally was not fused.

The first time I came across fused lighting was on a mid-sixties Austin

1100. Following several fires, an in-line fuse was introduced for the side/rear lights. It was hard to find, and initially not documented to either the trade, or to owners. Much consternation was caused when it blew!

So the answer to your speculative question is mid-sixties.

Automotive lamps do not have a fuse built in to the base like their mains- voltage cousins. Filament scatter on failure is therefore quite likely to cause the circuit fuse to blow. A single fuse for both rear lights would be a single point of failure that would be top of the list to eliminate from a safety POV.

Multiplexing has been gradually introduced since the late Eighties, so in that case there would be no extra wiring.

So would I, but I would also be surprised to see anything made this century that didn't have individual fuses for headlights, and for left/right position lamps.

Chris

Reply to
Chris Whelan

Found the wiring diagram. 12.12 digram 4.

formatting link
It's the first car I've seen like this. Didn't do it like this back in 1993. 200SX has one fuse for all side/tail/plate lamps. I don't like these modern wiring diagrams, they are so clunky that they can't show the WHOLE circuit but show a bulb and then have little "flags" "H4" "J4" because the fuse and relay are another graphic. But the lighting switch is missing and there isn't any sort of hint as to where that would be in the manual. Seems relay feed comes from the "CPU" so that puts the lighting switch in with the engine management system. Then because it's a completely rubbish way of showing electrical systems, diagram 2 "power distribution system has module 6 on it TWICE, just for a common earth between relay section and CPU.

Why 2 fuses? There is only one switch and relay.

Where is this Intelligent power distribution module? Its got a load of relays in it as well. Maybe it's the box to the LHS near bulkhead that I thought was the ECU?

THIS ISN'T HOW MODULAR WIRING IS SUPPOSED TO BE. There's supposed to be a module at the tail lamp, with one power feed and a can bus. Not a massive bundle of wires from the control switches to a single CPU and then a full 50Kg wiring loom hung off that.

Seems it's got 4 fuse boxes!

Reply to
Peter Hill

We had something in the sixties that had an overload self resetting cutout on the headlight circuit, much hilarity when the lights went out, then returned a couple of minutes later, repeat etc.

As to the micra, the odd thing is that it lists rear lamps individually on fuses and does not include front lamps, generally it is rh fr and rear plus no. plate on one fuse , lh fr and rear on another.

Reply to
MrCheerful

My CA Bedford had a thermal over-current device in the lighting switch. When it operated, it pulsed on/off about twice a second, meaning you had some lighting more or less working.

I noticed that; my guess is that it is actually split ns/os + no plate.

Chris

Reply to
Chris Whelan

...and where have the starting handles gone? ;-)

The wiring on modern cars are so complex, it needs to be broken down into sections.

It's how the wiring diagrams for things like industrial machinery is done also.

As I pointed out elsewhere in this thread, it's because a single fuse would be the biggest single point of failure.

I think I only saw three on Autodata.

BTW, was the fuse I mentioned blown?

Chris

Reply to
Chris Whelan

It might well have been something vauxhall or bedford, maybe a victor, I was only small at the time, so I don't really remember the timing or the vehicle, just that the lights went on and off by themselves. Back then we had several CAs (first vehicle I drove, at the age of 6, a very vivid memory !) Victors, vx 4/90s, Taunus 17ms, Jowett Javelin, Renault Dauphine, Citroen light 15, Cresta pas, Humber super snipes, loads of Hillmans, A60s, Minors, Imps, Minis, 1800s, 1300s, 1100s, Commas, J2s, Zephyrs, Mk2 jags, loads of vehicles, my father ran a car hire business and was not fussy about what went on hire, very successful too. I lent him a car to get back home in once and was somewhat surprised to find that he hired it out to someone for a few days, not actually my intention at all.

Reply to
MrCheerful

Dunno. Seems likely given the wiring to the number plate lamp.

I live in Burton on Trent. The Niece lives in Hemel Hempstead and presented the car at her sisters birthday in Calne Wiltshire. I'm not going to drive 100 miles just to find out. I won't see it again for a few months.

Just scotch locked a bit of wire from nearside to offside.

Reply to
Peter Hill

Front side lamps are on same fuses as the tail lamps, RH fuse 35, LH fuse 36.

Low beam RH fuse 40, LH fuse 39. But both share one relay.

High beam LH fuse 34, RH fuse 33. Individual relays.

Now the cunning bit is the day time lights, they put a relay in the common wire to the RH headlamp that switches from earth to a fused power feed. Then the power flows though the RH dip and it's fuse to the common dip beam relay, which is off, then back to the other fuse and LH dip beam to earth. As both main beam relays are off and independent there is no current though the main beam. So that's 3 fuses for 2 bulbs in series.

Reply to
Peter Hill

1 = 3 Fusible link holder Links A-E 2 = 4 Fuse box Links F-M, fuses 23-27 3 = 5 Fuse and relay box fuses 1-17 + Acc and blower relays 4 = 6 Intelligent power distribution module fuses 33-36, 38-40, 45-55

There are a number of fuse holders that are vacant, 21, 22, 28, 30, 31,

37, 40-44. But 18, 19, 20, 29, 30 are unaccounted for.

These new circuit diagrams are utterly useless as you have to look though every page for everything that one fuse feeds.

35 10A Sidelights, interior illumination 36 10A Sidelights, interior illumination

Fuse 35 also feeds the lighting for audio, heater, hazard warning, headlamp levelling, ash tray, ESP, headlamp wash and auto selector.

Fuse 36 also feeds the the light on door lock/unlock and heated seat switches (don't think she's got heated seats).

I may not have found them all.

Reply to
Peter Hill

OK. The fusible link box is not shown on Autodata, and does not contain what the manufacturer would consider 'user-replaceable' components.

That clearly isn't possible; some of those circuits individually would have a load greater than the 10A of F35/F36. I'm not sure haw you have arrived at the conclusion you have; perhaps you have followed the wiring 'through' multiplexing modules?

With the greatest of respect, I fear you are not reading the diagram you linked to correctly. (Unsurprising if you are not familiar with the format.)

Look *only* at page 4. At the top of the page, F35 points to H4, F36 to J4. At the bottom of the page, H4 and J4 connect to items 26 and 25 respectively. The key shows them to be the rear light clusters. A wire from

26 links to item 35, the number plate light.

By automotive standards, it's a pretty decent diagram.

Chris

Reply to
Chris Whelan

Pretty well all car electrics schematics have become too complicated to put in one page of any book for many a year. Even more so on the low grade paper so often used.

Only real answer is to re-draw them using vectors, and have as a PDF, etc. Which can be 'zoomed' in with no loss of detail.

Reply to
Dave Plowman (News)

Look at diagram 8 page 8 (12:22 of manual)

At top of page H8 and J8 are from the SAME fuses 35 and 36 and the tail lamp relay makes a 2nd appearance.

It is perfectly possible as they are for the switch and dash ILLUMINATION so the switches etc can be seen in the dark. 1 side lamp

5w, 1 tail lamp 5w, 1 plate lamp 5w, ?? switch lights 1.2-1.8w/LEDs, about 20-25W, less than 2 amps.

As illumination for heater controls, radio and headlamp levelling switch are on the suspect fuse 35, my Niece must think the car has now got a Xmas tree on its dash! If she had told me that there were no lights on the dash, I would have looked harder for a fuse.

This is a Girl with a Degree from UCL. I now suspect she has been driving with the interior lamp on so she can see the heater and radio controls. Or using the torch on the phone!

Reply to
Peter Hill
[...]

Yes, that would be perfectly normal for this type of diagram, both in automotive and industrial use. I understand how confusing this must seem when faced with it for the first time.

That's why I tried to persuade you to just look at the diagram for what you are tying to fix; it simply isn't possible to take in the 'whole picture' with that level of complexity.

Yep.

So I'm assuming that the fuse has been replaced, and all is well?

Years ago, one morning my BIL had a non-starting car. He carefully renewed the plugs, and HT leads, but it still wouldn't go. After spending much of the day on it, he rang me in desperation. I popped round, and immediately realised he had replaced the HT leads in a completely random order! He was somewhat embarrassed when I just put them on in the correct firing order, and it started straight away.

His degree is a First in Engineering...

Chris

Reply to
Chris Whelan

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.