No high beams

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pete98cobra

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Trying to help a friend with his expedition. A year ago he swapped out his headlight unit and it came with new bulbs. Well apparently a month or two ago the high beams stopped working . Fuse is good. I get 12v at fuse , but when I check plug for the bulb I’m only getting roughly 6v when high beams are turned on. Checked current at alternator and battery. Was thinking a bad relay, but unable to find one. Any help appreciated. Thanks
 

JayB66

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The OM should tell you what relay, and if more than one fuse is involved. Worst comes to worst find the Haynes Manual.
 

S20Workstation4

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Trying to help a friend with his expedition. A year ago he swapped out his headlight unit and it came with new bulbs. Well apparently a month or two ago the high beams stopped working . Fuse is good. I get 12v at fuse , but when I check plug for the bulb I’m only getting roughly 6v when high beams are turned on. Checked current at alternator and battery. Was thinking a bad relay, but unable to find one. Any help appreciated. Thanks
With the fuse being good, I assume that the High Beam Lamp turns on in the Instrument Cluster, right?

Does your flash-to-pass feature work? (Pulling the multi-function stalk towards you to flash)
The SJB continuously monitors the mult-function switch for a High-Beam Request when the headlamps are in the ON Position. When the Mutl-function/wiper stalk is pushed forward to the High-Beam position, the circuit is completed by being routed to ground
This then energizes the relay, which is in SJB.

The SJB High-Beam Relay is NON-SERVICEABLE. If the relay is bad, the entire SJB (BCM) has to be replaced. I don't think you have a bad relay in this case, due to the fact you are getting 6 volts at the headlamp connector when High-Beams are commanded on.

You most likely have excess resistance somewhere in the circuit.

Let me know if the High Beam indicator lights up on the IC, when you turn the High-Beams On. Your answer is crucial on what is next to diagnose. You don't want to have to be pulling apart the steering column to diagnose a bad Multi-function switch.....battling airbag connectors....etc


Joe
 
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pete98cobra

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Thank you for the response. I will check with my buddy and see if it works
 
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pete98cobra

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I sent him a message to do exactly what you said . He said headlights go out when he does flash to pass.
Since he is getting 6V . Would it be possible both bulbs went bad on high beams only ? He did buy aftermarket headlamps that came with pre installed bulbs. I will see if he wants to try to replace bulbs first before we dig deeper
 

S20Workstation4

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I sent him a message to do exactly what you said . He said headlights go out when he does flash to pass.
Since he is getting 6V . Would it be possible both bulbs went bad on high beams only ? He did buy aftermarket headlamps that came with pre installed bulbs. I will see if he wants to try to replace bulbs first before we dig deeper
I would say it is unlikely, but you could try replacing the bulbs. Did he install LED Aftermarket lights instead of Halogen?
 

BigOleFordFan

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If I were here, you would know it !
I would say it is unlikely, but you could try replacing the bulbs. Did he install LED Aftermarket lights instead of Halogen?
For a 2013, I seriously doubt that the aftermarket assemblies would come with LED Bulbs, if any bulbs at all....most of the ones I have seen say right in the product listing "bulbs NOT included"

The new assemblies I recently bought my '011 did not come with any bulbs, and they were fairly expensive @$400/set, which was fine by me, since I installed all LED's everywhere anyway.... low, high, turn, park, brake, reverse, license plate, 3rd row ect...

And I have had ZERO problems with any of them burning out or any other issues to date...
 
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