Turn signal light relay 1954 Drop head

Hello Folks,
I am working on the electrical system for an XK 120 drophead coupe 1954. When the turn signal comes on in the rear does it shut off the taillight or the brake light?

Thanks,

Wes Keyes

Wes:

When I was experiencing an issue with a signal/brake light some time back a friend following me told me that when I turned my signal on the brake light did not function on that side.

Chris.

Wes,

The DB-10 relay should interrupt the brake light when the indicator light is active, since you’ll still have the brake light at the other side. The tail light should never be interrupted (which is the 6W wire of the rear lamp).

Bob K.

1 Like

Many thanks Gents,

That is extremely helpful.

Wes Keyes

Presuming you have the 8 terminal DB10 double relay.
IMG_20210103_130359304
Here is how it works.


There are 3 contacts on each side.

When the turn signal lever is switched on, the relay on one side breaks one contact 22 and makes two others 23 & 18 or 21.
image

Wes:

Following Rob’s comments and further to my experience, the resolution of my particular issue (no RH signal) was to carefully clean all the contacts inside the box with emery cloth.

Chris.

Thanks for the comments. I think I am beginning to understand how it works.

Wes Keyes