Will my car pass an MOT with a dodgy fog light switch?
Discussion
I've been trying to figure out why my rear fog lights don't work on my Lexus RX400H.
If I bridge the relay, the lights come one. The relay works fine and has been tested.
In order for the trigger wire to be live, the stalk switch has to tell the ECU to turn them on via CAN, and if the ECU agrees, it will switch the relay on. It checks that the dipped light are on for example. For some reason, this isn't happening.
I've ordered a replacement second hand stalk to see if that fixes the issue, but I've got the MOT coming up very quick.
If I run a high amp switch to the relay port for now and just leave the switch dangling somewhere convenient for now, so the light can at least be operated, would this pass an MOT?
I know it's dodgy, but it's only temporary.
Can't afford for the car to be off the road.
If I bridge the relay, the lights come one. The relay works fine and has been tested.
In order for the trigger wire to be live, the stalk switch has to tell the ECU to turn them on via CAN, and if the ECU agrees, it will switch the relay on. It checks that the dipped light are on for example. For some reason, this isn't happening.
I've ordered a replacement second hand stalk to see if that fixes the issue, but I've got the MOT coming up very quick.
If I run a high amp switch to the relay port for now and just leave the switch dangling somewhere convenient for now, so the light can at least be operated, would this pass an MOT?
I know it's dodgy, but it's only temporary.
Can't afford for the car to be off the road.
There is a very useful thread for questions such as this
https://www.pistonheads.com/gassing/topic.asp?h=0&...
https://www.pistonheads.com/gassing/topic.asp?h=0&...
www.gov.uk/guidance/mot-inspection-manual-for-priv...
Section 4.5.3.
and Section 4.9 which deals with mandatory 'tell tales' for these lights.
If your arrangement doesn't have a tell tale as described it's a Major & fail.
Section 4.5.3.
and Section 4.9 which deals with mandatory 'tell tales' for these lights.
If your arrangement doesn't have a tell tale as described it's a Major & fail.
Edited by paintman on Monday 9th January 11:53
littlebasher said:
Funny, i did this a couple of years ago
Just ran an illuminated toggle switch direct to the relay and told the MOT tester that the foglight switch was the dodgy looking one dangling from the steering column.
He passed the car, so was at least acceptable to him !
^Just ran an illuminated toggle switch direct to the relay and told the MOT tester that the foglight switch was the dodgy looking one dangling from the steering column.
He passed the car, so was at least acceptable to him !
This
As long as the lights work it doesn't matter if the switch is temporary/dangling.
There's absolutely no reason any mot tester would fail it..
Draxindustries1 said:
littlebasher said:
Funny, i did this a couple of years ago
Just ran an illuminated toggle switch direct to the relay and told the MOT tester that the foglight switch was the dodgy looking one dangling from the steering column.
He passed the car, so was at least acceptable to him !
^Just ran an illuminated toggle switch direct to the relay and told the MOT tester that the foglight switch was the dodgy looking one dangling from the steering column.
He passed the car, so was at least acceptable to him !
This
As long as the lights work it doesn't matter if the switch is temporary/dangling.
There's absolutely no reason any mot tester would fail it..
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