Switched Power Issue

[JPB]

I bought and installed the line splitter described in 'Font of Wisdom; switched power the easy way' and everything works fine. However, if the battery charger is connected within one minute of turning-off the ignition, the switched power doesn't switch off so the auxilliary driving lights stay on. If I wait until the switched power has gone off the battery charger shows the error light.

Apart from adding rewiring the driving lights through the headlight circuit, can anyone suggest a solution?

 

[littleredrooster]

So.....why aren't the driving lights wired through the headlamp circuit then? Seems the logical way to do it (and the way 99% of aftermarket lights are wired)?

 

[Slowdown]

Take your switched feed for the lights from the rear light. You can't turn the rear light off, unlike the headlight. Although why you'd want to have driving lights and not the headlight is something else to debate.

Anyway, just a thought, like.

 

[Wapping]

I bought and installed the line splitter described in 'Font of Wisdom; switched power the easy way' and everything works fine. However, if the battery charger is connected within one minute of turning-off the ignition, the switched power doesn't switch off so the auxilliary driving lights stay on. If I wait until the switched power has gone off the battery charger shows the error light.

Apart from adding rewiring the driving lights through the headlight circuit, can anyone suggest a solution?

Are you using the BuMW 'Smart' charger?

 

[JPB]

Are you using the BuMW 'Smart' charger?

Yes. Interestingly, last night I disconnected the driving lights so I could connect the charger without running the lights all night and found it got very warm, something its never done before.

 

[JPB]

Take your switched feed for the lights from the rear light. You can't turn the rear light off, unlike the headlight. Although why you'd want to have driving lights and not the headlight is something else to debate.

Anyway, just a thought, like.

Thanks for the suggestion. I have driving lights on each side of a migsel bracket in addition to the headlight to create the 'triangle' effect, which is supposed to make a huge improvement in visibility to other traffic.

 

[Wapping]

I take it that your driving lights are permanently on when the ignition is on? Ie. The driving lights are powered from the auxiliary plug extension, with no switch in between?

If so:

(a) The BuMW 'smart' charger keeps the Canbus open, so the battery can charge.

(b) I can only assume that the charger is shoving umph into the battery and, as the circuit to the lights is 'open', it is powering the lights at the same time. That's a big draw on its resources, not surprising it's getting a touch warm.

 

[JPB]

I take it that your driving lights are permanently on when the ignition is on? Ie. The driving lights are powered from the auxiliary plug extension, with no switch in between?

If so:

(a) The BuMW 'smart' charger keeps the Canbus open, so the battery can charge.

(b) I can only assume that the charger is shoving umph into the battery and, as the circuit to the lights is 'open', it is powering the lights at the same time. That's a big draw on its resources, not surprising it's getting a touch warm.

Thanks Wapping! Yes, driving lights on with the ignition. The charger heating thing happened after I'd disconnected both lights, so I'd expected no big draw on the battery. However, when I tried again later, this time with the relay disconnected, everything worked fine. Looks like I shall have to add a switch between the line splitter and the relay.

Thanks to all for your comments and suggestions!

 

[Wapping]

Thanks Wapping! Yes, driving lights on with the ignition. The charger heating thing happened after I'd disconnected both lights, so I'd expected no big draw on the battery. However, when I tried again later, this time with the relay disconnected, everything worked fine. Looks like I shall have to add a switch between the line splitter and the relay.

Thanks to all for your comments and suggestions!

No problem.

Yes, a switch is the answer. You can see the switch in the wiring diagram below, in place before the relay of course.

It will mean you will have to remember to switch the driving lights off each time you use the BuMW charger.

I think I would power the driving lights from the rear light feed. That way:

1. They are automatically on with the ignition, which is what you want.

2. They are automatically off with the ignition, which is what you want.

3. You avoid the extra switch.