Number plate light failure

[Aga]

I have a 2005 facelift ZT. I highlighted this problem ages ago on the "old site", but never managed to fully resolve the intermittent problem of the rear number plate light failure.
Had the car services on 10 March and asked the garage to resolve the problem once and for all - lo and behold, since getting it back it is no longer an intermittent problem. It is now permanent!!!
They say they cannot find the problem!!!!
HELP!!!!!
Any suggestions?

[Simon]

Mine's the same.

Dodgy wiring connectors and bulb holders.

I'm thinking of "making my own" holders and replacing the OEM units.


As a fix though you can remove the outter see-tru covers via the screws on them and remove the bulbs then squeeze the connectors together slightly, then replace the bulbs. Removing the whole units involves removing the boot lid lining.

Come to think of it, I might have a go at 'fixing' the problem tomorrow... I'll let everyone know if I get around to having a look at it....

[mach1rob]

Maybe also worth looking at the wiring around the hinges, has been known on some of the older models for the wiring to split, allowing the wire to short to earth or break connection entirely.

[eu53zxr]

Snap - I had the same problem - I gave up with the garage in the end & took the lining out the top of the boot lid & removed the boot spolier - small lip version on my car, so only a 10mm bolt either end - once removed you can then carefully remove the number plate light holder from the spoiler - mine was stuck on with double sided foam. The bulb holder connections are generally dirty - so clean up with a small screw driver & some sandpaper, you can then inspect the circuit connections - mine were both loose & this is what was causing the problem. So 10 mins with soldiering iron re connecting across the track did the trick. You can re plug the connection for the rear lights onto the board before re fitting to check it all works o.k.

You need a nice day a few cups of coffee - but all worh it in the end - mines been fine for 3 months now (fingers crossed) give it a go - what have you got to loose ? (apart from the nuts holding the spoiler & a big lump of skin of the back of yor hand)

[Keith]

As above first eliminate if you have a break in the wiring
easy enough to check if you have a cheap meter

then it is well worth the effort to strip out the entire lamp assembly

The two bulb holder are mounted on a small pcb and joined by tracks to the connectors for the cables on mine one of the tracks had broken which I bridged with a bit of wire for a permanent fix.

Boot lid liner is easy to remove spoiler and lamp holder are both held on with bolts and double sided tape which requires a good bit of pulling to undo so take your time.

Garages are a waste of time for these type of problem they could do a proper job but the time to do so would have you reeling at the bill hence why they probably fobbed you off.

[KENHAYES247]

Hello all,

Has anybody had this problem before? My rear LH Number plate has stopped working. I had no indication from the onboard computer. I changed the bulb but it still does not work. When i removed the rear right bulb (which is working) the onboard computer picked it up.

So i guess the bulb is not at fault but maybe the circuit, especially as its not picked up by the onboard check?

Before i start removing the boot lid liner are there any other checks worth doing?

Many thanks:bowdown:

Ken Hayes

[Aga]

Put it into the "shop" as it was baffling me! They were unable to fix it on the first visit - it appears that "the whole light unit is rusted away". Hard to believe on an '05 car!
Any views on these comments from the gararge?

[Simon]

Rust could develop if the units werent sealed properly from the factory. I must admit I'm not over impressed with the design of the number plate lights and one of these days I'm going to get round to taking the whole thing out and putting in my own bulb holders/wiring. I seem to get bulb failure warnings every few weeks or so and it's nearly always the number plate lights.... :rant:

[Simon]

The cars bulb-failure light will only illuminate when both bulbs have failed. By removing the one working one, you have caused the car to think neither work and therefore activate the bulb-failure light.

As for remedies, then the whole bulb holders and associated wiring are all a bit hit-and-miss in our cars. If you remove the transparent covers you can squeeze the terminals of the bulb holder together to ensure they grip the bulbs better. You can also remove the entire unit but doing so involves removing the boot lining and accessing them from behind (ie from inside the boot side). Often it is not the bulbs that have failed but just the terminals that have come loose.

[black olive]

the units are a bit pants, the conductors are riveted phosphor bronze, and the riveted bits corrode/ loosen.

I has this on one of my lampholders, but couldnt get my spoiler off to remove the unit, so soldered a fine wire from the relevant terminal to the affected lamp holder terminal ( hope this makes sense- no pics)

[black olive]

Ive just replied to the thread below.

http://www.the75andztclub.co.uk/forum/showthread.php?t=5418

two threads going at once !!

[Simon]

Some mod may end up merging them! :poke:

[black olive]

could do with getting hold of a batch of light units and modifying them:lol:

[Simon]

I've seen a few bulb holders from various companies that I've thought would do as subsitutes (can't remember who or what now, as I wasn't particular looking for a reason when I saw them, if you get what I mean). Anyway, it would then be a case of wiring them up. Difficult bit could be removing the unit from the car in the first place (as others have noted) plus maybe getting the 'new' lamps to fit snuggly in place..... :shrug:

[black olive]

the problem I had was removing the unit, the spoiler was well and truly glued to the bootlid, and I envisaged snapping the thing in half :SHOCKED:

fortunately by removing the MG badge holder I could get at the central terminals to solder the wire to

[Simon]

On my Zed with the larger spoiler I too noticed that I needed to remove it (the spoiler) to remove the number plate light plinth at the time I couldn't be bothered with doing that and it also looked as if glue/sealant was used around the spoiler where it meets the boot lid - something which will require me having new sealer to hand if I decide to undertake this task.

[Aga]

Took it into the "shop". They stated that "fault traced to the printed circuit board being in a corroded condition".
As a result, they had to "remove board and clean and make good connections. Refit board and all removed parts".
They also added "Any further problems then a new number plate light printed circuit board will be needed".

The light worked for a few days, however, something now rattles in the boot lid when I open & close the boot. Also, it has now regained the fault, so I am back to square one!

Where would I get a PCB for the light, anyone?

[Aga]

Got into car this morning & would not start! Flat battery!
Took it to same shop & they stated that boot light is permanently on!
Would this have been something that was created when they took my boot apart to access the number plate light? (They also scratched my lip spoiler and boot ld when they did their stuff, but they say it will buff out!!
Advice please!!!

[Keith]

A replacement bulb holder is about £17!
if they scratched the car then they can buff it out or fix it!

Boot light is operated by a microswitch in the lock
could be a coincidence!

[Keith]

Some mod may end up merging them! :poke:

Merged Smudged or whatever :)

[Simon]

Merged Smudged or whatever :)

So they have :p:

They also scratched my lip spoiler and boot lid when they did their stuff, but they say it will buff out!!

A replacement bulb holder is about £17!
if they scratched the car then they can buff it out or fix it!

As Keith says - if they scratched it, then they can repair it. At absolutely no cost to you. If they moan about it, take it up with Trading Standards. ;)

[Aga]

Got into car this morning & would not start! Flat battery!
Took it to same shop & they stated that boot light is permanently on!
Would this have been something that was created when they took my boot apart to access the number plate light? (They also scratched my lip spoiler and boot ld when they did their stuff, but they say it will buff out!!
Advice please!!!

Got into car yesterday and again - no charge! !
Caled the garage & they jumped it and got me on my way.
Booked it in for a proper fix on tuesday (along with a new PCB for the number plate light fitting) and they are now saying that it may be the battery! Damn it! It's only 18 months old!!
It there another area that could lead to draining the battery overnight?

[Aga]

HELP!!!
My battery is now totally flat!
Not even the usual clicks when you turn on ignition and the key fob does not work.
Worse still, my alarm keeps going off! I have disconnected the battery (it was flat anyway) but this has not stopped it!
I am in danger of causing grief top my neighbpours if this is not resolved by tonight!!!
HELP PLEASE!!!!!!

[JohnDotCom]

You most probally have the optional extra seperate Battery backed up alarm horn to detect when battery disconnected or if main alarm unpowered. This is situated under the Plenum scuttle. I've had this go off myself so know it can be a pain but is of course very useful to.
A new battery should cure your problems they are very reliant on a good battery and any loss of power causes all sorts of faults to appear.

[David3807]

Do you have SAt Nav or any electric toys in the boot.

I seem to remember a couple of threads where a sat nav was not switching off as it should thereby draining the battery.

Given that you have had skilled (Unskilled ???) labour poking around in the boot area might be worth a check.

Can you re charge the battery and put it back on the car.
Then you can use the remote to unlock the car and de activate alarm. Then if you lock the car using the key only I believe the alarm will not be set. That might appease the neigbours a little !!

Have to say not sure if that will work when you have the battery back up but worth a try.

[Aga]

Don't have Sat Nav in boot (came with Smart Nav) but I do have a boot 6-changer! Other thread seems to point to that as a possible culprit!

[Aga]

Quick update.
The "shop" managed to replace the PCB in the end and also sorted the scratches out. No problems with the light now!
However, they have not recponnected the boot light (they originally thought that this may have been the reason for the deadening of the battery!)
They were neant to do this at the same time as sorting out the replacement PCB, so I will have to take it in again (they will do it free of charge)

[Jules]

Boo
I had a saloon 04 Plate last month with no number plate lamp function.
Off with the UPPER boot lining revealed a black plug and socket where one bulb holder is paralleled off to the other.

With boot slamming and the fact the loom was not tied to anything, the weight of the loom had jerked the connectors apart.

SOLUTION:
Refit connector and cable tie the loom in various places behind the lining.
They won't come out again