light switch wiring 56 merc

[Johnnydidd]

I am ready to install the head light switch, what do the letter mean? light switch OFF D&B are common. 1st position B&D&R&I&P are all common. 2nd position B&D&H&R&I. Question why are B&D the same? I assume B stand for battery, What is D? next I assume H stands headlights, R tail light, P stands for parking lights, I stands for instrument lights. THANKS John

 

[oldave57]

I think the "D" terminal is for the dome lamp. The attached schematic of the light switch (for my 57 Ford, but should be the same for the Merc) shows the "B" terminal (which is the connection to the battery) on an un-switched direct connection to the "interior lights" terminal. On this schematic, there is no "D" designation for that terminal, but it is an un-switched, fused connection which makes sense because the dome light will come on even with the light switch in the "off" position. Also attached is a "domelight and stoplight diagram" which shows a 9 amp fuse between the battery terminal and the interior lights terminal.

Hope this helps. It should be okay (and when you install the new switch, you can remove the wires from the old one and install on the new one kind of sequentially so you know they are going to the same terminals).

Dave

 

[Johnnydidd]

thanks Old Dave, sounds good to me, I thought it was hooked to the voltage regulator so the amperage doesn't have go through the amp meter