Forum Discussion

Antigua1767's avatar
Antigua1767
Explorer
Jun 05, 2013

Just a flicker...and only a small one

I had two halogen reverse lights installed by the dealer on the back bumper of the fifth. I drove off without checking them. Got home and they don't work when hooked up to the dually.
I brought the trailer back to the dealer.
1. Techy attached a wire to the fifth 7 prong. One to the battery power and then one to the reverse lights. (lit up like Christmas) - techy said it was a vehicle issue.
2. I had a bed plug wired into the dually without the trailer present. All sockets working...including the reverse socket. I get home...hook up the fifth wire connection to the trailer wire connection without attaching the trailer and no lights....actually the halogen lights give a very slight flicker...like they want to go...but just won't.

Any suggestion or home remedies before I bring both back to the dealer?
Respectfully,
Andy May

9 Replies

  • Antigua1767's avatar
    Antigua1767
    Explorer
    Jun 12, 2013
    Just a quick update.... Had a relay installed. Also a switch inside the trailer. Looks like Las Vegas at night behind the trailer. It is also a great help at night with the reverse camera.
    Again Thanks for the suggestions and advice,
    Respectfully,
    Am
  • riggsp's avatar
    riggsp
    Explorer
    Jun 06, 2013
    Halogen lights require a high starting voltage and current to operate...probably more than the backup light switch can handle...I would install a relay so the backup light switch only "sees" the low current needed to activate the relay and then full battery voltage through the relay to the lights.
  • Wayne_Dohnal's avatar
    Wayne_Dohnal
    Explorer
    Jun 05, 2013
    Here's something that may or may not apply. On the Sprinter chassis, the Signal Acquisition and Actuation Module is always measuring the current drawn by each lighting circuit, and if too high, it shuts it down. If one hooks an extra bulb on something like the backup light circuit, the bulbs give but a brief flicker when the circuit is activated. Mercedes left enough headroom in the current limit to drive a relay, which is the documented solution in the Sprinter Body Builder Book. Your truck is a 2008. That's when Chrysler and Mercedes were connected (my Sprinter is officially a 2008 Dodge). Maybe there was some platform technology sharing here? Just a thought.
  • Antigua1767's avatar
    Antigua1767
    Explorer
    Jun 05, 2013
    Again Thanks...I did forget to mention that there are two halogen bulbs in each light, so four bulbs at the back in two light fixtures...will get if checked.
    Respectfully,
    Andy May
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Jun 05, 2013
    I agree with the "The switch does not have the current carrying capacity" and Chris Bryant just gave you the solution.
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Jun 05, 2013
    Usually we put a relay on the trailer and power the halogens from the battery rather than the tow vehicle. It's pretty easy to do where the 7 way cord hooks to the rig. You can also put a switch here to light them up.
  • Antigua1767's avatar
    Antigua1767
    Explorer
    Jun 05, 2013
    Both logical....
    Thank you.

    Should I consider exchanging them with LED lights,
    Respectfully
    Andy May
  • camperpaul's avatar
    camperpaul
    Explorer
    Jun 05, 2013
    It sounds like you are tripping a self resetting circuit breaker in the TV.

    As a test, try disconnecting one of the backup lights (this will cut the current in half) and see what happens when you put the TV into reverse.
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Jun 05, 2013
    The reverse switch may not have the capacity to light a couple of halogen bulbs, or it could be a ground issue.

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