I have just put my car back together for its 1st MOT (under my ownership) and have just discovered a problem that I have inherited from the last owner.

 

Initially the side lights and headlights were working OK. Go to main beams and the RH headlight went out. I looked further and found that the 15A fuse for the RH headlight was missing (surely without this fuse the headlight should not have worked at all). Replacing the fuse and the main beams worked....yay!! Unfortunately this then meant that the dip beams did not work!!. The previous owner obviously lost his headlights but discovered that removing the fuse fixed the problem in the short term!!! Anyone had this before or have any ideas?

 

Just to add to the question...may seem a stupid question but mine is a UK car and is equipped with 2 bulbs in each of the headlight units.....what is the outer one for? I have never had these working...is this model complete with Dim Dip? are the 2 connected to my problem?

 

Thanks for any advice on this....has to be sorted for the MOT!!!

Dave

 

Let me get this right. The bulbs on the outer part of the h/lights are not working? is this right? They are the normal driving lights you would would use if you were driving along at night.

 

The bulbs for the larger part of the H/L is for when you want to flash someone. If these come on when you turn your lkight on normally, and you are not able to turn them off, then something is defo not right.

 

I have had a fair few headlights apart in my time and one thing I know is that the outer bulbs can be a bit of a basterd to seat right and they also pop quite easily do to heat build up. 55W isn't too bad but if you start increasing to 100w or even 130. You will be lucky to get 1-2 months of use out of each bulb. There are the exceptions though.

 

I can see that you are from the Staffs area, where abouts? If you aren't too far, you can pop up to mine on saturday if you like and we can both stand around stratching our heads if want.

 

 

Cheers

Cos

I believe that the head light relays are of the change over type. This means that if the relays are either knackered or missing live or earth in the correct places then the system will do very strange things. Put the fuse back in and make sure that all of the fuses are present and correct. Try pulling the relays in the engine compartment fuse box and making sure the terminals are not corroded. Also make sure that the earths to the headlight bulbs are OK, this could be caused by a bad earth.

 

Try these suggestions, if you still have no luck then I will look at the wiring diagram for you.

 

Paul

 

p.s have you got a multi meter?

It appears that the bulb in the main larger part is used for both. Normal driving lights and they are on low...put the main beams on and they get brighter!!!! (well at least one anyway). Got the circuit diagrams from the on-line manual and there are 2 types...cars fitted with dim dip and those without. We (my dad aswell) couldn't even figure out which one was fitted to my car. All the wiring is there for the outer bulbs but we have been unable to get them into life at all. Seems as though there is a big problem as the headlamps will only work on high beam when both fuses are in...

 

Where abouts are you in staffs? I'm in Lichfield....although Sat will be a little late. Bought the car with front accident damage and therefore it had no MOT. Everything is back together now so it has to go to the garage for the MOT...so I may well have to see what they have to say about it!!! Car is not road legal at the moment :(

We have pulled the relays and we do get some strange results, although they do not appear to have any corrosion at all. Pulled the Dim relay and main headlights still seemed to work (seems strange to me!!). Pulled the RH relay and when we put the meter across the contacts we got the main beams on!!! The headlights still worked. Pulled the LH relay and everything stopped working. Do you know what was fitted to the UK spec cars? There are a number of wiring diagrams available for different models.....

 

Electrical systems in cars make no sense at all.....they do not conform to any of the electrical standards...a law unto themself!!!

Electrical systems in cars make no sense at all.....they do not conform to any of the electrical standards...a law unto themself!!!

LMAO, and each manufacturer has their own way of doing the same thing, and then the French have a go for a bit of a laugh!.

 

As far as I know UK cars from 87 sold in the UK are required to have a dim dip system, therefore your car should have dim dip.

 

The first thing you must do is to make sure that everything is working OK (ie relays, fuses and switches) on their own. I dont know if the relays are interchangable with another relay from a different circuit (ie not lighting), if they are then swap them around and see if anything is affected.

 

Once you have checked the basics then check the earths, if you have a bad earth then the wierdest of things can happen.

 

 

Paul

Might seem obvious (sorry) but have you checked the fuse inside the car (block next to accelerator pedal)? Do the rear lights work? If these are not working, and you get funny dip-main beam action then this is the first place I'd look...found this from dodgy stereo installation, of all things.

 

HTH

 

StuartR

http://www.300zx.co.uk/cgi-bin/manual.cgi?list=el&dir=&config=&refresh=&slide=40&cycle=off&scale=0&design=default&total=133

 

Looks like you may well have a bad main/dipped beam relay. There are 3 relays in total for the headlights, one for each side (for both main and dipped), and one for dipped/main beam (serves BOTH units).

 

Try swapping it with another relay to see if that solves your problem ;)

 

HTH

 

CheerZ,

 

Andy

And this shows you where the dimmer relay is in the box ;)

 

http://www.300zx.co.uk/cgi-bin/manual.cgi?list=el&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=110&design=default&total=133

Stuart,

 

Must admit haven't checked the fuses in the car...the rear lights do work but its funny you should mention a dodgy stereo installation. When I was working on the car I found a cable trailed between the passenger wing and the body and then attached directly to the battery (with an inline fuse). They had obviously taken the unit out but left the crap installation. Anything could be wrong at this point!!!

Andy,

 

We have been playing with the three relays but couldn't get the main headlights to work at all. What do you reckon I am looking at to get a set of second hand relays?

 

In addition to the info I left last night....it looks as though the previous owner had been using the dimmed part of the dim dip system as his main headlights. So far we have been unable to get any activity out of the main headlights!!!! Some very strange things going on.

Next step is to see if mimicking the relay makes the lights work then. Find which connections it makes for main and dipped beam and simply bridge those connections in the relay box with a short length of wire - carefull you get it right though cos if you get it wrong, you could have a fire on your hands - if the fuse didn't pop anyway... ;)

Originally posted by andyduff

And this shows you where the dimmer relay is in the box ;)

 

http://www.300zx.co.uk/cgi-bin/manual.cgi?list=el&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=110&design=default&total=133

 

LMAO - I've had my Z for nearly 2 years now and always had temperamental dim dip for ever. However, when trying to find the source of the problem, I've never understood why when I remove the relay that says "Dim", the lights remain on dim and don't go out. ....and now I know.

 

You learn something new everyday.