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Topic: Headlamp HI/Low relay mod **complete (Read 2918 times) previous topic - next topic

Headlamp HI/Low relay mod **complete

Why do i have headlamp power out to my headlamps with the "multifuncion switch unhooked?

before i go any further, i need to know how this is even possible.

if someone isnt busy and explain it over the phone, it would be easier for me in the shop doing this mod.

304 772 3411

otherwise, i think i best back off for a moment

Headlamp HI/Low relay mod **complete

Reply #1 –
88bird 5.0
has auto lamp / auto dim which is turned off

Headlamp HI/Low relay mod **complete

Reply #2 –
auto lamp ckt although its not on?

Headlamp HI/Low relay mod **complete

Reply #3 –
Check out the "headlight dimmer relay" in your EVTM. With the main light switch on you will have headlight power. The M/F switch picks or drops the relay. With M/F switch disconnected, the dimmer relay will be dropped and you will have hi-beams.
Looks like the dimmer relay may be drawn wrong in the EVTM. I think it should show hi-beams on the picked side and low beams on the dropped side. So you should have low beams with the M/F switch disconnected.

Headlamp HI/Low relay mod **complete

Reply #4 –
correct softtouch, i agree to that as well, I do only have low beams.

The circuit in queston is the red/yellow off the main light switch.
There are two red/yellows bonded to one terminal.
one red yellow goes to the m/f sw
one red yellow branches off and out to the auto lamp circuit(s)

Its starting to look like my initial drawing of the relay mod for Hi/Lo beam mod may be best thus using one relay only.

Headlamp HI/Low relay mod **complete

Reply #5 –
Yes all you need is one relay!! In the LOW position you ave a cut through and in high when energized you have HI. This also has a fail safe feature if the relay coil fails. You still have low beams to get you home in the dark. Just saying!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Headlamp HI/Low relay mod **complete

Reply #6 –
hmmm,,, interesting,  I didnt look at it like that.

Headlamp HI/Low relay mod **complete

Reply #7 –
I think the self reseting circuit breaker in the main headlight switch is also a safety feature. With an overload it heats up and opens, then cools and closes. You have the lights flashing on and off. With a fuse you just have off.

Headlamp HI/Low relay mod **complete

Reply #8 –
Thanks, its nice to know there is a built in redundant circuit, i wasnt expecting to have headlamps at all with the MF sw lying on the floor board.

Headlamp HI/Low relay mod **complete

Reply #9 –
we have decided to move forward and build our relay bank and fused power source for my son's bird.
see pics below, they pretty much explain themselves.

Mason wants to option for a single headlamp relay in between the main light switch and the MF switch per my very first option i drafted up.
Mason also picked the separate marker lamp relay option as the one and only drafted version thus far.
the third relay shown is a place holder for future ign switch work.

You all may know already the mounting bar i am fixed to and we have an additional 8awg ground bonding jumper in the mix to insure this removeable part keeps its ground.

we are using smart fuses to light up if they blow.  Mason wants to end up with the capability to have 6 relays to groom in circuits with maximum redunduncy.

one picture shows two white shims on the back of the fuse block, the way the block is designed and we need shims, i used some spare non conductive nuts from a nonconductive nut/bolt kit i had lying around.  The fuse block has exposed parts and we made sure there were no chances of arching to our mounting bracket.

Headlamp HI/Low relay mod **complete

Reply #10 –
a couple more shots
Again, the kid likes to have maximum redunduncy.

Headlamp HI/Low relay mod **complete

Reply #11 –
another shot remaining, its layout allows for a total of six relays.
the fuse block is something you can find at advance in either a three or six position layout.

Headlamp HI/Low relay mod **complete

Reply #12 –
The very first time I dealt with smart fuses, I didn't even know they existed.  I started checking for power in the back of a Windstar at the REM, one power was only showing 2.6v. Booger in the circuit, right?  Seen it a hundred times, pulled the seats and detrimmed the back of the van, opened the harness checked all the splices and connectors, in the end I found this blown fuse with a light on inside.  The fuse was pinned under a plug, so at first check, I didn't notice any light, once everything else was eliminated, and I'm on the point of condemning the fuse box for water intrusion. I notice a faint little light coming from a crevice in the box, I pull this plug out with a fuse clipped inside when I examined the fuse I realized how a blown fuse had sent me on a wild goose chase looking for a high resistance.  The light doesn't load the circuit enough to not let volts down circuit.  I was pissed.  Now, whenever I see them I swap them out for regular ones.  Blown or not.  I figure they won't trick ME again, but I might save some other tech the same headache.  I'm starting to build a decent collection of them.

Headlamp HI/Low relay mod **complete

Reply #13 –
Good idea having the dedicated ground. I like it!

Headlamp HI/Low relay mod **complete

Reply #14 –
Hey Foe
I will have to keep that in mind, I'll blow a fuse and see what the circuit acts like.  I see your point, would also drive me nuts.