I’m just noticing some slight misting inside both Headlamp Units of our 2009 Mk3.5, This doesn’t change when lights are left on for a while or in recent very hot spells. Not a problem as yet but I wonder if any one out there has resolved this.
Regards Chris
It’s not happened to Cariad as yet, I’ve got my fingers crossed. Sorry, can not help.
Gales
The chances are that the lens has begun to detach from the plastic body.
I’ve had this with several different makes of cars and on all four corners, usually either as a result of someone giving the lamp cluster a knock or from simple old age and dissimilar materials being repeatedly temperature cycled. In some instances it is possible to find the crack and reseal it with a suitable adhesive (silicone, vinyl, ABS etc - varies depending on glass or which of several different kinds of plastics). For example on my old Astra the original Hella headlamp responded well to silicone but (after Honourable No2 Daughter drove into the brick gatepost) the later Bosch ones refused to stay glued when they began to leak.
Sometimes (rarely) it is there simply because it got in during a bulb change and was trapped there after the back was resealed.
More often it means a new lamp housing, but you should be able to swap across all the bulbs and fittings etc unless the damp has allowed them to become too badly tarnished/oxidised.
Good luck.
Mazda will say it’s normal to have the occasional condensation due to changes in humidity etc, I believe there’s a U.S technical service bulletin on this issue
Hmm, in my experience (fortunately not with Mazda headlamps as yet) once the damp gets in the reflectors begin to degrade, and apart from making it more difficult to see where you are going it is then an MOT failure.
I think Mazda has an excuse for most things these days , anything to avoid a warranty claim.
Hmm, while the pdf says not to use hot air because of melting, in fact one should use a stream of the coldest air possible as this will still absorb moisture if not already at 100% humidity. Hot air has the potential to carry more moisture in.
I use a GoPro to video skiing and always leave it open outside before a shoot to freeze off and reach minimum humidity to prevent fogging. If one seals it in the warm humid hotel room and then goes outside the fog on the optics is total within a minute or so.
However, back to the cars, once the air in the lamp cluster has been dried there should be no fresh moisture introduced so no fogging. On my GM lamps (thirty+ years of them) the only times they have had any condensation was when there was a leak, the rest of the time they have always remained clear, partly because there is an airtight rubber seal on the back where the sockets are. I know this because I was commuting either 10 or 38 miles each way each day and needed to check and clean the lights mirrors and windows before almost every journey.
On my Mk3 MX5 headlight cluster the main and dip beams have rubber seals, but I’m not convinced by the arrangements for the sidelight or indicator or the levelling motor, and when driving in heavy rain there will be some water around these, and as the air in the light cluster expands when hot and contracts when cold it could easily draw in some of that wet film when the heat from the headlights is turned off.
So yes, I expect there could be some condensation in the MX5 lamps after being used in wet weather. But I would also expect it to go away, slowly, as the car as a whole dries out.
This is something to be aware of.
Thanks for the pointer to a possible future problem.