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Flashing Units burned...

dondel

Freshman Member
Offline
Dear all,

I have an issue with the flashing lights, or better, with the flashing unit.
My BJ8 has dual lights, front and back.
It looks strongly like I have a short circuit somewhere.

As I understand the wiring diagram, the flashing lights are connected via the direction switch to the battery (passing over the ignition).
I only noticed this burning only while driving, so that I had the following thoughts:
- Is the voltage changing while driving? Would be strange as other electrical parts don't show problems;
- Are the wires creating a short circuit due to the vibrations?
- Electrical connections oxidised!?

I added between the direction switch and the flashing unit a (far too big) 10A fuse in order to not burn all the time the unit. In fact on each side of the car only 21W should be needed + 5W for the unit, (P=U*I -> 26W =12V*2.17A).
Did already somebody else have an issue with the direction lights and could give me an (better) idea where to search?

Thanks for your help!!
 

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dondel said:
.... I only noticed this burning only while driving, ....
.... I added between the direction switch and the flashing unit a (far too big) 10A fuse in order to not burn all the time the unit. ///

Do you notice this burning all the time while driving ?
Or do you only notice it when using the turn signals ?
Does using the left or right seem to make it worse ?
~
You definitely have a short circuit. You need to isolate and then check with an ohm meter to ground the left and then the right circuit looking for a short to ground. Once you figure out which leg is shorted, follow the wire carefully along it's length looking for worn through insulation, especially where the wires go through holes in the body. That is the most likely location for the short.
In addition to the four circuits feeding the turn signal lights, check the common wire going to both of the dash indicator lights. That wire could also be shorted where it goes through the firewall.

Ed
 
dondel said:
In fact on each side of the car only 21W should be needed + 5W for the unit, (P=U*I -> 26W =12V*2.17A).
One small note, each turn signal is 21W, so front and back on one side would be 42W. You might also check where the wires come out of the steering column at the front. The stator tube is kinda sharp and can wear through the wire insulation.
 
Thanks for your advises and corrections!

I checked last week again the circuits and found out that I don't need to drive to create strange behaviour on the flashing unit.
When the engine is off, I couldn't find any problems on the flashing.
When the engine is running, not when driving, the indicator lights start suddently blinking both, randomly.
I will check over the weekend the voltage control box for a correct setting. It could be that the unit is not set correctly and that it causes trouble. It could perhaps be that the over voltage harms the flashing unit but is not really seen on the other electrical parts. What do you guys think?
 
dondel said:
the indicator lights start suddently blinking both, randomly

When you say that, do you mean both sides flash like hazard lights?

I won't rule out the regulator, but I agree with Ed in checking for a short first. Without the resistance of the bulbs, the flasher relay will heat up quicker causing that fast blinking.
 
hi ,check that it is wired up correctly,generally the flasher unit is as follows Bterminal to switched live L terminal to indicator switch and P terminal to the dash indicator lights,but it sounds as though the problem is with the actual indicator switch or the wires from it shorting and having all 4 lights flashing will burn an ordinary flasher unit out .Don't think that it is your voltage regulator as this would affect the gauges aswell
 
GregW said:
dondel said:
the indicator lights start suddently blinking both, randomly

When you say that, do you mean both sides flash like hazard lights?

I won't rule out the regulator, but I agree with Ed in checking for a short first. Without the resistance of the bulbs, the flasher relay will heat up quicker causing that fast blinking.

What I meant was that the indicator lights, on the dashboard start blinking both. The indicator lights as such blink normally until the additional fuse blows.

I will try to find a short first. Thanks for your help till now!
 
mikespain said:
hi ,check that it is wired up correctly,generally the flasher unit is as follows Bterminal to switched live L terminal to indicator switch and P terminal to the dash indicator lights,but it sounds as though the problem is with the actual indicator switch or the wires from it shorting and having all 4 lights flashing will burn an ordinary flasher unit out .Don't think that it is your voltage regulator as this would affect the gauges aswell
The connections are correct. It is that the 2 indicators on the dash blink both, sometimes the wrong one (left indicators, but right dashlight or vice-versa) till the additional fuse blows.
Concerning the regulator, haven't tested it yet. I will not change the settings... Thanks for your help!
 
dondel said:
When the engine is running, not when driving, the indicator lights start suddently blinking both, randomly.
Hi Dondel,
One more question for you: Is the random blinking happening only when the turn switch on the steering wheel is used? Or does it happen whenever.
 
Hi GregW,
I haven't tried the flashing unit without the switch on the steering wheel. It seems to me strange that there is a difference between running engine and not. I can also be that I didn't observed it with engine off; but this does not mean that the behaviour isn't the same...

So your guess is that the switch on the steering weel could cause the trubble? I thought already that perhaps the wires in the steering wheel could be the root of the issue...
 
mikespain said:
Don't think that it is your voltage regulator as this would affect the gauges aswell
A question on that quote: Aren't there seperate voltage regulators for the gauges? Or are they all directly connected to the central one?
 
dondel said:
So your guess is that the switch on the steering weel could cause the trubble? I thought already that perhaps the wires in the steering wheel could be the root of the issue...
It is strange that only the dash lights flash together (like hazards), not the turn signals at the 4 corners of the car. My first suspect would be the green/purple wire that goes from both dash indicators to the flasher relay.

Here's a photo of how I found my flasher wired up.
 

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