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Hi all, I have a problem of fluctuating voltage on the rear three 12v interior lights in my van. Sometimes they will operate but most of the time they just have a faint glow or flicker as the voltage drops below 12v. I have tried running a new earth from a chasis point to the negative terminal of the light but no difference.I have used an analog meter to monitor the voltage and sometimes it can drop as low as 2 volts when switching on a light.

The other central 12v lights and accessories all work fine.

One strange thing I've noticed on the meter is when a light is switched off, the voltage drops slowly as if it was being discharged through a capacitor unlike the others which show an instant zero at switch off. All three light units work 100% from the battery.

Any help would be appreciated.

Thanks in advance...

George.

Hi Michael and Stuart. Thanks for the reply, but my fault when I said 12v, that was just a general figure. The reading was above 12v but not quite 13v. I had just recently charged my battery (which is also trickle charged from a solar cell) from a stand alone heavy duty charger and all but the three units at the rear end of the van are all working 100%. I felt sure that those three had their own separate earth but that wasnt the case.

Many thanks

George

Hi Michael. I know all the units are working fine because I've tested them all straight from the battery.

I decided to take a wire straight from a 12v feed in the back of the control unit, across the floor,to one of the light units and hey presto all three are 100%.

This tells me that the 12v + line is not good as I've tested the Negative (earth) and thats  fine. That only leaves me with the task of running a + wire to one of three units as they are all in parallel. Not looking forward to drilling holes holes but there's no other way.

Thanks again.

George