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Turn Signal Woes

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TodE

Jedi Hopeful
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Finishing up restoration of a 1955 BN-1. I have replaced the wiring harness, used a new electronic signal box (Moss) (why they had to make it so complex???) new parking light Lucas sockets. I am using LED rear tail light bulbs with standard 1157 parking light bulbs. A regular (non electronic) flasher (I think new?) With no ballasts installed. Positive ground.

My problem is all the lights come on, but the left side parking light and tail light is 3 times brighter than the right side with no turn signal flash, left or right??

1.) I had a problem with the wiring coming from the trafficator, but when I disconnect the 3 wires (4th which is horn is OK) from the trafficator, it makes no difference, same as above.

2.) I replaced the rear LED's with 1157's and it does not change anything. Brighter left than right with no turn signal flash.

Here's what I am thinking: 1.) Better ground? 2.) Bad electronic signal box? 3.) Possible wires hooked up wrong at the signal box?

I am asking the experts for help or someone who has had similar problems????

Thank you in advance for any comments.
 
I would say it is probably number 3. double check all the connections for the correct routing and try jumping the wires at the front by-passing the traficator to eliminate that as a problem.
 
TodE:

I have a BT-7, and had a similar problem. The culprit was that the stop/tail lamp assemblies were wired backward. With the headlamps turned on, the tail lamp circuit illuminated the brighter brake/turn signal filament. When the turn signal or brake lamp circuit was engaged, it illuminated the tail lamp filament (much dimmer), which couldn't be seen because the much brighter tail lamp filament was already lit. Not sure if BN-1 wiring is similar, and I don't have an electronic box, nor LED's in the stop/tail lamp assemblies.

Hope this helps.

Jerry
 
Jerry is right. You have the wires going to the wrong contacts on the bulb - fix by trial and error. The fronts have the same chance of being wrong too.
 
terp83 said:
TodE:

I have a BT-7, and had a similar problem. The culprit was that the stop/tail lamp assemblies were wired backward. With the headlamps turned on, the tail lamp circuit illuminated the brighter brake/turn signal filament. When the turn signal or brake lamp circuit was engaged, it illuminated the tail lamp filament (much dimmer), which couldn't be seen because the much brighter tail lamp filament was already lit. Not sure if BN-1 wiring is similar, and I don't have an electronic box, nor LED's in the stop/tail lamp assemblies.

Hope this helps.

Jerry
Click to expand...
A common mistake is using the wrong bulbs in the sockets. Unfortunately some bulbs interchange in the sockets but the lighting is a another issue. I just went through a troubleshooting process with my rear lights acting up after reassembling my BJ8. Changing bulbs finally fixed the problem. I used bulbs that the P/N's were worn off and this contributed to the source of the problem.
 
Hi Todd,

First, am I correct in understanding that your trafficator relay box is electronic? Also, is the bulbs brightness greater because both filaments are activated?

If both filaments in the bulbs on one side of the car (front and rear) are being activated, I would first check the connections of the flasher as a short between terminal “B” and “L” will activate the signal filament without flashing. If the problem persists with a different flasher installed, I would then look at the wiring of the trafficator relay box.

To check the trafficator relay’s function, I would first check the connections and, if all looks correct, exchange the wiring for the left indicator lights with the right indicator lights. The relay box could be the problem if the issue moves to the opposite side.

Although there could be an issue with a bare wire or connector being fed from another circuit, this cause is usually rare if all worked properly prior. But it still remains a possibility.

Hope this helps,
Ray (64BJ8P1)
 
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I have a 60 BN7 with positive ground. Last year, I put LEDs on both front and rear parking lights as well as converting the flasher to work with the LEDs. The issue is finding a solution that will work with positive ground. I had bought 2 different sets of LEDs from SB in which one set was polarized, the other non-polarized. The recommended LED flasher (red) was also bought and then upon installing everything, I experienced what you are describing. Also the flasher wouldn't work in correct rhythm. After many months, I located Classic Auto Lights website (Oregon). I talked with the inventor. I purchased what was needed. The LEDs were not cheap. The LEDs came with a info sheet that recommended the correct flasher and resistors. You will need (2) RL-650 (12V) 50W resistors and a 3 or 2 prong mechanical flasher. If you need these items, I have extra (2) resistors, and 2 or 3 prong correct flashers. I over bought what I needed. At the same time during all this update, I put LEDs in the instrument panel (that's another story). I do have extra LED bulbs I bought from SB. The intent of this thread is let you know what I experienced. The extra items are for anyone to purchase if needed.

This might help.

Mert
 
Had the same problem with my BN-1 when installing all original equipment and a new loom. Bright filaments were reverse activated on one side of the car until I rewired them and then all lights worked correctly. (park, turn, stop.) In other words the wires on drivers side go to one set of terminals on the bulb holder; the wires on passenger side are reversed.
 
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