400/450SE Lighting...
Discussion
Following on from the thread about preventing the headlamp pods lifting on sidelights only, I'd perused the factory wiring diagram to see how the lights were controlled on those models and realised there are some significant changes from the earlier cars.
Not content with a scrawled A4 sketch I've waved a graphics tablet at it and come up with this:
which might make tracing glitches a little easier
Note that most of the control switching is done at the 0v/earth/ground side of the relays rather than the 12v or 'live' side as is usual.
Oddly, the rear fogs are fed directly from the dash switch and not via a relay
! The headlamp main beams and the driving lamps are permanently linked unlike on the earlier cars where the driver had the option of adding the extra illumination. The later circuitry means that the driving lamps perform the 'flash' function - although the main beams do actually light when 'flashed', the pods stay retracted. There's now only one diode in the control circuit and its function is to bring the pods up when the headlamps are switched on. If you were to find the pods lifting on sidelights and then dropping back down as you put the headlights on, suspect the diode. You can't simply snip the diode out,however, to stop the pods lifting on sidelights because they then won't come up on headlights either!
Edited to improve image quality!
Not content with a scrawled A4 sketch I've waved a graphics tablet at it and come up with this:
which might make tracing glitches a little easier
Note that most of the control switching is done at the 0v/earth/ground side of the relays rather than the 12v or 'live' side as is usual.
Oddly, the rear fogs are fed directly from the dash switch and not via a relay
! The headlamp main beams and the driving lamps are permanently linked unlike on the earlier cars where the driver had the option of adding the extra illumination. The later circuitry means that the driving lamps perform the 'flash' function - although the main beams do actually light when 'flashed', the pods stay retracted. There's now only one diode in the control circuit and its function is to bring the pods up when the headlamps are switched on. If you were to find the pods lifting on sidelights and then dropping back down as you put the headlights on, suspect the diode. You can't simply snip the diode out,however, to stop the pods lifting on sidelights because they then won't come up on headlights either!Edited to improve image quality!
Edited by Wedg1e on Thursday 14th May 02:03
mrzigazaga said:
So could the White/Yellow be snipped out from the "Lift and Lower" and then wired to the white of the cowling light switch...
What is it that you want to do? Make the pods come up when you flash the headlamps? My guess is that they did away with it because the pods can't react fast enough when you flash the lights so they opted to use the driving lamps instead. What would make more sense would be to mod. the earlier cars (350s and 390s at any rate) to leave the pods down and flash the drives/front fogs instead... it looks 'tidier' My car's wired to flash the drives as well as the headlamps but the drives haven't been connected for over 12 years so I have to leave the pods in circuit.
Well mine flashes the driving lamps but i would like to have separate sidelights without the lamely lit pods coming up..Don't want to just cut wires!...I would prefer a separate switch for the sidelights or position 1. Sidelights...Position 2. Headlamps..If its too much faffing around then i will leave as is..Don't do much night driving anyway...
mrzigazaga said:
Well mine flashes the driving lamps but i would like to have separate sidelights without the lamely lit pods coming up..Don't want to just cut wires!...I would prefer a separate switch for the sidelights or position 1. Sidelights...Position 2. Headlamps..If its too much faffing around then i will leave as is..Don't do much night driving anyway...
Right, don't use that wiring diagram above then 'cos I doubt it'll apply to your car 
My car leaves the pods down on sidelights only so on yours it may just be a diode snip that's needed. Sounds like you have dim-dip as well?
Wedg1e said:
Sounds like you have dim-dip as well?
Yeah..Then when the headlight switch is on position 2 the main beam comes on..If i flash then the driving lights and the headlights flash although at night it seems like the N/S headlamp is going off when i flash..Need to have a look at that..Wasn't dim/dipped headlights a load of shyte?...
I think i would still prefer to just have sidelights = Position 1 and Headlights and pods up on position 2.
I will have to remove the cowling to see what is there and what is connected to what...Cheers...Ziga
mrzigazaga said:
I think i would still prefer to just have sidelights = Position 1 and Headlights and pods up on position 2.
I will have to remove the cowling to see what is there and what is connected to what...Cheers...Ziga
Should be easy enough... assuming you have the SD1 column then I imagine it'll look a bit like the diagram on my webbie, but with a dim-dip unit thrown in I will have to remove the cowling to see what is there and what is connected to what...Cheers...Ziga
I notice that the diagrams in the Heath book fail to mention dim-dip altogether, so that won't help you
Wedg1e said:
mrzigazaga said:
I think i would still prefer to just have sidelights = Position 1 and Headlights and pods up on position 2.
I will have to remove the cowling to see what is there and what is connected to what...Cheers...Ziga
Should be easy enough... assuming you have the SD1 column then I imagine it'll look a bit like the diagram on my webbie, but with a dim-dip unit thrown in I will have to remove the cowling to see what is there and what is connected to what...Cheers...Ziga
I notice that the diagrams in the Heath book fail to mention dim-dip altogether, so that won't help you
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