Multifunction (high beam / turn signals) switch keeps failing

Topic: Multifunction (high beam / turn signals) switch keeps failing (Read 5848 times) previous topic - next topic

Multifunction (high beam / turn signals) switch keeps failing

Reply #15 – January 31, 2015, 10:24:21 AM

both of you are not completely correct, neither of you are addressing the root cause.
just being blunt.
You both are right when speaking to a car that has a pull out plunger type headlamp switch!,, like in 83/84

Most of us have a rocker switch,, with a 2'' wide and 3'' long and 3/8'' thick finned heat sync mounted to the headlamp rocker switch.
Path of power for light stuff:

the marker lamps - fuse panel to main light switch to >front=home run wiring to bulbs, >rear=fuse panel to home run wiring to bulbs
-here at the main light switch is makes sense as shown on our drawing links that it makes sense to slave near the main light switch.

the headlamps - fuse panel to main light switch to multifunction switch to home run wiring to bulbs
-the headlamps being slaved at the main light switch does fully slave out the entire headlamp circuit.

putting the headlamp relays in the engine bay does effectively remove the wattage from the above interior parts I would think, I did not want to introduce additional heat , water or things like that to my critical circuits. maybe that's why they are placed inside the cabin was my thought.

building out a relay bank and placing it where I did allowed me to intercept and connect all existing wiring without cutting anything, it was a centralized spot to pull back from both the main light switch and from the multifunction switch the wiring which was long enough to be tied to slave relay coil triggers. furthermore home run to bulb wiring was also long enough to be plugged into the high current side output of each separated relay.

and while I was at it, all the existing ign and accy wiring was also long enough to be extracted and reconnected to the slave relay bank.
this is why I chose a relay bank,,,, yet there is nothing wrong with placement as you chose, this was just my choice.

again, the thread is about headlamps so putting a relay to the headlamp switch just so the headlamp switch triggers a slave relay ground for power delivery out to headlamps only cures some of the problem of resistance and old parts partially bad ect. What you are asking he does is what I have drawn in my "headlamp relay mod option 2 rev0".... and you will see what the down side is to it., it is only taking care of half the problem. Your example picture shows a mustang switch with no huge heat sync,,so.......... lets compare apples to apples.. mentioning or eluding to the idea its the same as a TC is very odd coming from you. seems you would care to mention they are two different heat designs.

the way I show it is "how its dun" tom,,, if your interested in perfection with zero variables remaining on the table to "allow" headlamps to screw up again. otherwise the way you do it is half way there. keep trying ,, and yes,, im just shop talkin ball bustin and not really more than fun havin..

Multifunction (high beam / turn signals) switch keeps failing

Reply #16 – January 31, 2015, 10:35:15 AM

for auto lamps, its a different animal and documented as well.

Multifunction (high beam / turn signals) switch keeps failing

Reply #17 – February 01, 2015, 11:04:48 AM

I think we had a working diode and jumper mod to slave the headlamps through the Autolamp relays. I'm still using it, no problems.

Multifunction (high beam / turn signals) switch keeps failing

Reply #18 – February 01, 2015, 11:00:23 PM

Yes me too no problems

That drawing rendition is also in the link

One diode was too low of a wattage but I increased both diodes in size but other than that no issues

Tom where is your overcurrent protection for the high and low side of those relays??

Multifunction (high beam / turn signals) switch keeps failing

Reply #19 – February 02, 2015, 07:50:37 PM

Jay the way i salve mine is correct because it protects the switch as well as the multi function switch. I well know the switch can not handle high current.I use 2 relays for the fog lamp circuit to remove it from the switch as well Other than that my new truck came yesterday and i am so dam happy i could die. Love it!!! By the way J i remove the bias resistor on the instrument panel. Doing this eliminates the need for heat sync and it getting hot from high current . If in dead you want dimming feature you can remove the bias resistor on the back of the dash and the switch will run cool as a cumber. If the dash lamps are run full brite you can bypass the switch completely as i do on my mods The heat sync is for dimming the dash lights and it only gets hot if dimming. also make sure the resistor on the dash is removed not necessary and a heavy current load. Further more installing LED lamps in the dash,cures the issue 100% as they do not draw high current and do not add to high current through the headlight switch. With that i am going for a cruse in my new RIDE VROOOOOOOOOOOOOOOOMMMMM!!!

Multifunction (high beam / turn signals) switch keeps failing

Reply #20 – February 03, 2015, 06:20:37 AM

I also don't see any difference between pull type and rocker type headlamp switch. Both designs are pr0ne to failure and for both of them (as well as for multifunction switch) is better to use a relay mod to keep them cool.

Multifunction (high beam / turn signals) switch keeps failing

Reply #21 – February 03, 2015, 12:39:22 PM

JUUUUUUST great.

Something ELSE I wanna do now! This looks fantastic! Good job!