Rear fog lights and MOT

[peter_m7uk]

I see that the IVA manual section 28 states "The rear fog lamp(s) must only illuminate when dipped beam, main beam or front fog lamps are lit".

However, the MOT inspection manual section 4.5 states "Front and rear fog lamps are permitted to operate independently of any other lamps or ignition systems" and "Rear fog lamps may extinguish when main-beam is switched on or when dipped beam headlamps are switched off".

This says to me that the IVA and MOT rules are different!  The fog lamp can be independent of any other lamp for MOT.   I'm asking because I got an advisory on the fog lamp when I passed the IVA, as it could turn on any time I pressed the button.  My first MOT is due next year, but it seems like this operation is actually okay???

[Bob Tucker]

Theres a big difference between "may" and "must"......personally I'd go with the IVA manual. All the production cars ive driven can only turn on the fog light when the main or dip are on. As soon as you turn them off the fog light goes out too.

[alanrichey]

28 minutes ago, Bob Tucker said:

All the production cars ive driven can only turn on the fog light when the main or dip are on. As soon as you turn them off the fog light goes out too.

And as far as I'm aware, they must NOT turn back on next time the headlights are switched on, you have to have some sort of latching system.    Having said that, this requirement was introduced relativley recently so many of our cars to not need to comply.

[Kerry]

Sorry Alan, that is not correct they can stay on. 
The rear fogs I thought only come on with dipped beam ?

[alanrichey]

Are you sure ?   This a quote from Car Builder Solutions (I know they are trying to sell their module, but I would be surprised if they weren't telling the truth:

NEW IVA REAR FOG RULES 

In June 2013 the rules for switching on and off your Rear Fog Lights changed.   Now, the Rear Fog lamps must only be lit when the Dipped Beam, Main Beam or Front Fog lamps are lit. The Rear Fog Lamps may continue to operate until the other lights are switched off. The rear fog lamps must then remain off, even if the other lights are switched on again, until they are deliberately switched on again. This is to prevent people driving off to work in the morning with the rear fog lights glaring after forgetting to switch them off the foggy evening before.

 

[toriitom]

5 hours ago, alanrichey said:

The rear fog lamps must then remain off, even if the other lights are switched on again, until they are deliberately switched on again. This is to prevent people driving off to work in the morning with the rear fog lights glaring after forgetting to switch them off the foggy evening before.

That was my understanding of the changes made in the rules. AFAIA that is what happens in any cars manufactured after 2013.

[Bob Tucker]

My 1993 Mondeo latched the fog light off when you turned off the headlights. That makes  more sense than leaving the fog lights activated.
But hey, this is the DVLA we're talking about!

[peter_m7uk]

Thanks for all the replies.  So yes, my rear fog light turns on with the sidelights or dipped/main beam.   Also, if you turn the lights off and back on again, the fog lamp comes back on again, you don't have to relatch it.   Anyone else's do that??

However, that sounds okay for MOT, which is what I'm interested in  -  MOT inspection manual: cars and passenger vehicles - 4. Lamps, reflectors and electrical equipment - Guidance - GOV.UK (www.gov.uk)

[IanS]

My rear fog light works the same as yours.

It is wired exactly the same as in the 1983 sierra doner and works the same.

I have never had any problem with it at MOT time, on the road in 1997 and tested every year since.

[nelmo]

On 11/20/2023 at 1:48 PM, peter_m7uk said:

This says to me that the IVA and MOT rules are different! 

Absolutely - IVA is the test that is also used for when, say, Ford want to introduce a new model. It is a much more thorough, demanding test than an MOT which is just a check for basic safety, really.

My fog light also stays on if you turn the other lights off and on again - been through 3 MOTs with no problems.

Edited November 21, 2023 by nelmo

[phil lilley]

Fog lights for the mot can work completely independent of any other lamp or ignition.  You can simply wire them to an on/of switch. They dont even need to be ignition live.                        

MOT rules and regulations are separate and often contrary to the iva test. So if you want an answer to an mot related question you should always disregard anything except the MOT inspection manual and guide. 

 

Just to add, dont for a moment assume anything in or not in  the MOT test is related to logic.  I have been a tester over 30 years and some of the stuff still baffles me. 

Edited November 22, 2023 by phil lilley

[peter_m7uk]

Thanks all for the advice.  I feel fairly confident now to just go to MOT as it is  

[peter_m7uk]

Just browsing back and thought I'd update.  It passed the MOT just fine 

[Kerry]