low voltage at back up lights

[dsvarczkopf]

Here's another odd question.

I was repairing my aux. back up lights that I have hooked into my regular ones. I blew my test light bulb so went to my volt meter. I was reading only 7. 5-8. 5 volts at the bulb sockets. I took one out and hooked up to a 12 volt source and what a difference. We all know that this is a weak link anyway, and now to have only partial voltage..... Is there a relay somewhere that jumps the voltage down. Everything else is working fine, battery's are up to snuff at 12. 5 without engine running, 14 running. any idea's?

 

[illflem]

If the bulbs themselves were on when you measured the voltage the problem probably lies in too many watts for too small of wire. The voltage should be 12 volts, if you disconnect the bulbs and still get a low reading you may have a damaged wire.

 

[Cooker]

I'm with illflem.



What gauge wire do you have feeding the lights? Or maybe you don't have them wired through a relay at all? IF you have them running off the back up light circuit only, this is definitely your problem. Aux. backup lights should really be put on their own circuit with a relay, fed with no less than 14 gauge wire.



-Ryan

 

[Ram4Sam]

Check all the grounds for good contact, rust/paint/crud ... .



Sam

 

[redneckdr]

aux backup lights

also, did you disconnect the original lights when you put the aux's on? if you are still feeding the oem's and aux lights with the puny wire from dc, that may be the problem. i suggest you wire the aux lights to a relay. if you have the oem trailer light wiring, you have a 12v+ source there, and a backup light lead in the harness. use the bu light wire to trigger a relay fed 12v+ from the harness. with good grounds, you'll probably be amazed at the increase in light.