Need some help, electrical issue

[kkaa]

Getting close to the end of the restoration and so far so good, except this...

I noticed my headlamp dip switch was loose, tightened and when i put power back on, crackle and a wiff of smoke. I blew the 50 amp fuse, replaced, pulled out the switch and checked the wires and tried again.

I now have no headlamps, no instrument lights except for indicator, no wiper, It seems anything off the 50 amp is not working. I checked with a meter on the 50 amp post 11.9 amps only when the ignition switch is on, and the 35 amp post is 12.2, i think this is correct??

I pulled out the dash switch, checked continuity and seems ok. Beeps one way and not the other.

Any help??? did i burn out the headlap switch?

 

[Healey Nut]

Dissconnect the wires going to the switch on the firewall , put in a new fuse and see if all the other stuff works ,then use your meter on continuity and see if the wires to the switch are shorted etc .

 

[GregW]

Couple things that jump out to me. For stock wiring, the 50 amp fuse is for the horn only. The headlights aren't on a fuse at all.

 

[kkaa]

Guys, horn working. Weird.... I thought the horn was on the 35 amp? Should I disconnect the wires on the headlamp switch and for testing connect the red and green eliminating the switch ?

 

[kkaa]

In this link to a wiring diagram from Andrea, its the lighting switch. Should i pull the wires and connect them to test the switch? That switch seems to connect to all the dash lights too, which are out at the moment.

I do have a meter and can test from the post on the switch that takes in the red but dont know what I would be looking for. Any advice would be great....

https://picasaweb.google.com/112770819864514987162/DropBox?noredirect=1#5848222494024288690

 

[TimK]

Getting close to the end of the restoration and so far so good, except this...

I noticed my headlamp dip switch was loose, tightened and when i put power back on, crackle and a wiff of smoke. I blew the 50 amp fuse, replaced, pulled out the switch and checked the wires and tried again.

I now have no headlamps, no instrument lights except for indicator, no wiper, It seems anything off the 50 amp is not working. I checked with a meter on the 50 amp post 11.9 amps only when the ignition switch is on, and the 35 amp post is 12.2, i think this is correct??

I pulled out the dash switch, checked continuity and seems ok. Beeps one way and not the other.

Any help??? did i burn out the headlap switch?

Back to basics: The 50 amp fuse is supposed to connect the A1 post to the A2 post on the fuse block. This only powers the horn and is not switched by the ignition switch, ie. it is hot all the time. The 35 amp fuse connects the A3 post to the A4 post of the fuse block and is switched (by the ignition switch). The headlamp dimmer does not feed from the fuse block but from the A1 post of the voltage regulator to the lighting switch to the dimmer switch then to the headlamps. How you blew the 50 amp fuse is a mystery. Get a wiring diagram and analyze your symptoms considering flow of power. Also make sure the fuses are in the right place and not misplaced connecting the A1/A2 side with the A3/A4 side.

 

[GregW]

connect the red and green eliminating the switch ?

No, the red wires feed the dash lights and the running lights. Green wires are fused hot and turn on with the ignition. The blue wire is the main headlight wire that gets it's feed from a brown wire at the headlight dash switch. As Tim says, that brown wire comes from the regulator.

 

[kkaa]

Makes sense, thank you for that guys. Is there a test with the voltage regulator I should try? I pulled the headlamp switch and wired them together, so not that.

When I turn on the key i get fuel pump, fuel gauge, horn, no wiper no lights, no wiper....

No, the red wires feed the dash lights and the running lights. Green wires are fused hot and turn on with the ignition. The blue wire is the main headlight wire that gets it's feed from a brown wire at the headlight dash switch. As Tim says, that brown wire comes from the regulator.

 

[GregW]

I'm confused as to where you are. Was everything working before you tightened the dipswitch or are you starting to test a new installation after a restoration?

Getting close to the end of the restoration and so far so good, except this...

I noticed my headlamp dip switch was loose, tightened and when i put power back on, crackle and a wiff of smoke. I blew the 50 amp fuse, replaced, pulled out the switch and checked the wires and tried again.

I think you mean volts here?

I checked with a meter on the 50 amp post 11.9 amps only when the ignition switch is on, and the 35 amp post is 12.2, i think this is correct??

 

[kkaa]

I was at the buttoning up stage, everything was working. I just wanted to be sure everything was tight, HAHAHA. All the lights worked, headlamps, wipers, it all was fine at that point. I wanted to turn on the key once i was done to be sure one more time and got a crackle smoke and popped the 50amp fuse. Not sure what exactly happened but a wire from the under dash dip switch was loose and could have been how i ended up here.

I'm confused as to where you are. Was everything working before you tightened the dipswitch or are you starting to test a new installation after a restoration?


Yes, volts....

I think you mean volts here?

 

[GregW]

What is weird to me is the fuel gauge works, but the wipers don't. Those should be on the same fuse. To answer your regulator question, if you have power to other things, chances are the regulator is fine. Have you checked for voltage coming into the dipswitch with the dash switch on?

Where do you have power coming from for the dash light switch, the regulator or the fuse block?

 

[AH100M]

IS your wiring harness good? Original/replaced with a quality one? Funny color wires in random places? Ones waving in the breeze?

Also, check all the grounds. Instrument panel, engine compartment, anyplace there's a black wire with a ring on the end that's supposed to secure to a metal portion of the chassis or body. Including the main ground strap.

 

[kkaa]

Thanks so much for the help on this..

Its all stock bn-7 wiring and after this will put in the relays. In the meantime, i can check the voltage coming into the switch. FYI, i just pulled tach and spedo to check the grounds, that seemed fine...

What is weird to me is the fuel gauge works, but the wipers don't. Those should be on the same fuse. To answer your regulator question, if you have power to other things, chances are the regulator is fine. Have you checked for voltage coming into the dipswitch with the dash switch on?

Where do you have power coming from for the dash light switch, the regulator or the fuse block?

 

[bob hughes]

My money is on the regulator.



Bob

 

[kkaa]

You could be right. Is there a simple test for the unit to see if its faulty???

I guess were looking for a quick test that if x doesnt get power its y as your issue. We, (me and the kids) have a meter without much experience tracking the issues down. If anyone has any ideas or can call us, please IM me and will shoot over my cell....Thank you...

My money is on the regulator.



Bob

 

[kkaa]

I suppose its the right time to fix my issue and come out ahead so just bought 5 in-line fuse harnesses. Does anyone have a cheat sheet of where to actually locate them?

OD - 10 amp
tail - 15 amp
License - 15 amp
Horn - 20 amp
fuel - 10 amp

 

[RAC68]

First, the 35amp and 50amp English standard original Lucas fuses translate to 17amp and 35amp using fuses available in the US. The difference is in the way they react to a short so reduce the amperage to the US equivalents if that is what you are using. Second, put them in the correct slots on the fuse box as previously mentioned by Greg as you could be applying enough power to you switched circuits easily have them burn .

The original harness wiring is quit thin and never designed to handle the amperage used with today’s headlights, etc. Age and corrosion further deteriorates its flow potential and induces higher resistance resulting in heat and further accelerated oxidation. To address these conditions, I would clean and solder all bullets and install dielectric grease in all connectors before inserting.

Simple Analyzing Tool and Procedure
Before analyzing and/or testing the circuits in question, I would acquire an inexpensive manually-reset Circuit Breaker (with connector) and attach a bullet on both contact wires. A second unit, created from an in-line fuse setup and extra fuses, will also come in handy to isolate a questionable component during testing. As you continue your investigation into the causes of your present problem, disconnect the original connection from the power source and install the circuit breaker in between. If the breaker flips when power is applied, reset the breaker, disconnect all outputs, and test again. If the breaker again flips, the problem is the component. If not, move the breaker to the output circuit and connect the inline fuse unit to the input and test. If the breaker flips, move all to the in-line fuse to the input connector of the next unit and test to see if the breaker flips. If it does and the fuse remains good, the fault is in the line between the switch output and the next component. Using both units allows me to definitively identify the location of the fault validate the correction with at low risk.

I realize this is a tedious task but, without finding something obvious, and not yet having installed fuses to narrow the issue, this is the procedure I have followed with success.

Directory of Fuses
To address this type of issue, I have installed quite a number of in-line fuses to protect all major components/circuits. Although some think I have gone overboard, the smaller the affected domain of an issue, the faster the problem will be identified and fixed. Since in-line fuses can be easily installed, or added over time, into a specific circuit and hidden, I have resorted to creating a fuse directory of function/component/circuit protected, location, and amperage to help jog my memory after years of nothing happening.

Definitely Install Relays
Also, since the original gauge of wire used in the Healey was never designed to handle today’s electrical loads, I have also installed relays to power the headlights, driving lights, horn (yet to be completed), and sound system to with new heavier wiring installed to power these components. Original wiring is not only used to switching the relays and, therefore, carries a significantly lower amperage.

Again, this is the processes I would follow and hope you find your faults very soon. Grounding is an issue often encountered when something doesn’t work and there is no short in the circuit so don’t forget to carefully examine for a bad ground when something doesn’t work.

Good luck,
Ray (64BJ8P1)

 

[Keoke]

Go back to the dip switch wich let all the smoke out initially and look for your problem there.
The insulation on an associated wire should show signs of being over heated and may lead you in the correct direction.

 

[kkaa]

I think we found it, headlamp switch!!! With all the advice i went back to square 1 and when testing the headlamp switch. On the back, the BROWN/BLUE on post a registered 12v, but it wouldnt allow it to jump to S1 or S2. When i direct wired them by removing the switch and used a butt connector the lights came on....

Heres the switch. Didnt notice any scorch marks but the cylinder on the inside looked very warned..

Thank you everyone.... Now, were adding in all the inline fuses and will post a couple pics.....

Go back to the dip switch which let all the smoke out initially and look for your problem there.
The insulation on an associated wire should show signs of being over heated and may lead you in the correct direction.

 

[Keoke]

Now, were adding in all the inline fuses and will post a couple pics....

Since you now know the switch acts as a good fuse you should install a relay to activate the head lights.
Then all the load the switch sees is the relay coil.