Electrical Question

[baja1d]

Finally getting the 40 on the road but have an electrical gremlin. When driving w/o my lights on all turn signals work appropriately. However, when I turn on my head lights, my left blinker will not flash- burns solid. Right turn signal blinks normal w/ head lights on. Any ideas?

 

[Pulso]

I had the exact same issue recently and I did two things to correct it, and I'm not sure which was the main problem:
First, the light that wouldn't flash had an 8w bulb so I swapped it with a 25w.
Second, the two plugs that connect to the light were reversed. I flipped them and everything worked perfectly!
Hopefully your problem is that simple.

 

[flaa1a]

Yeah. Check and replace the bulbs in your signal indicators in your dash (not the bulbs on the fenders).....and check your grounds in the light buckets. I found that if one light was burnt out it kind of threw the whole headlight blinker brake lights our of wack.

There are a couple of good write ups on the forum.

I had the exact same problem in my 55.

Randy

 

[bikersmurf]

Not likely bulbs because they work until you turn on the headlights.

I'd say GROUND.

https://forum.ih8mud.com/40-55-series-tech/415151-never-underestimate-importance-ground.html


That's a link.

 

[Pin_Head]

X2 They likely share a bad ground.

 

[baja1d]

Thanks for the direction. I was thinking that it might be a ground issue due to my experience with trailers, however, I can't just run down to Harbor Freight and buy a $15 pair of lights.

 

[bikersmurf]

My best guess would be the harness grounds... 1) right front fender 2) inside right frame rail under gas tank

 

[Pin_Head]

The turn signals (location depending on year) are grounded through the fender sheet metal to the frame and the front bib. It seems likely that the fender-frame ground is bad and that the turn lamp is grounding through the bolts connecting the fender to the bib, where the headlights are grounded. The headlight ground is also probably corroded and bad, so that when you turn them on, the headlight has a potential above ground that is not letting enough current flow through the turn signal to trip the flasher.

 

[primer7]

easy to check the ground, just run a wire from the non functioning light outside case to another ground point to make a quick check.

FWIW, I had a simular issue and found that the bulb had a "Cracked" filament...you could always swap bulbs as well.

 

[John McVicker]

Don't waste anymore time, it's the ground. Fix it & your problem will be solved.

John

 

[rusty_tlc]

It sounds more like a short from the marker light to the turn signal light to me.

 

[Pulso]

Did you fix it?

 

[baja1d]

Nope

Not yet. Briefly looked at it yesterday but spend most of the day stripping a '65 to was scheduled to be crushed today. Despite my best efforts to change his mind, the owner was a guys that just bought old rigs for pennies so that he could sell them for scrap. Tub was shot but I did get the instrument cluster, both fenders, hood, heater, front bib, and alternator for a decent price.

 

[bj40green]

Not likely bulbs because they work until you turn on the headlights.

I'd say GROUND.

https://forum.ih8mud.com/40-55-series-tech/415151-never-underestimate-importance-ground.html


That's a link.

Bikersmurf is right. The current find it's (bad or missing) ground going through another light, in this case the turn signal.

 

[baja1d]

Alright, finally got some time to look at things. In the process of cleaning grounds I discovered that the PO had attempted to wire in some trailer lights. I believe that this is my issue. I've looked at my wiring schematic and still can't get things to work 100%. So here it is:

Running to the rear of the vehicle is four wires:

1. Green with yellow stripe
2. Green with red stripe
3. Solid green
4. Green with white stripe

At this point I'm pretty frustrated. Can anyone tell me the combination of these 4 wires. This is what I tought it was:

1. Green with yellow stripe (Stop lights)
2. Green with red stripe: (Head lights & Left Turn signal)
3. Solid green (Ground)
4. Green with white stripe (Head lights & Right Turn signal)

With this combination, everything works except my rear amber lights when the headlights are on. BTW this is a 1964 FJ40.

 

[destin]

lemme know if this helps, form the FSM

let me know if this helps

[IMG]http://farm6.static.flickr.com/5215/5385231873_84368fdb3b_b.jpg[/IMG]

the GY ( green & yellow )wire on the passenger side controls the passenger side blinker.
The GO ( green & orange ) wire on the driver side rear controls the driver side flasher.

The solid green on either side i believe is for running lights.

Solid green also controls the license plate light :0

oh and btw, the GW wire that is near the license plate light, that is your trailer brake light, for if you are running a trailer

 

[baja1d]

Nice and bright. Most everyone said it was a ground and after hours of cleaning and trying different combinations of wires Destin's post got me thinking about my tail lights. I didn't remember seeing a ground wire on one of my 300+ trips down onto the creeper so I thought I'd take a closer look. As it turns out, there is no ground wire because they're grounded through the mounting bolts to the frame. Apperantly after 47 years they can become very corroded. I'm not sure if this was my main issue because of all the other corrective actions I took but it's very likely. If there is a "next time" this is where I'll start and I'm confident that it will only take a couple of hours rather then a day and a half!

 

[destin]

glad you sorted it man

Yeah the rear lights ground to the mounting bracket and frame, if they get funky they no worky

Cool man!