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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3362
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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I got a 2007 peterbilt 379 and i want to know how to ad a

Customer Question

hi i got a 2007 peterbilt 379 and i want to know how to ad a relay for the high beam
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 1 year ago.

My name is ***** ***** I will assist you.

You should already have relays for the low and high beams.

The cycling is because you have regular relays. I suggest going to NAPA and tell them you need a "high amp output" relay to swap for the relays that you currently have. What is happening is either the relays or the circuit breakers are getting too hot from the new lights with the higher output and they are cycling. You wrote that you already changed the fuse so the next step is to swap the low output relays for high output ones. A lot of times they are gray in color instead of black.

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Customer: replied 1 year ago.
There is a fuse panel by my feet on the driver side with 2 self reset fuses pertaining to the headlights but no relays on that panel whatsoever, then behind the speedometer panel on dash is some relays but none pertaining to headlights. I have called several Peterbilt dealers and according to them that model I got don't have a relay on the headlights, don't make sense to me but anyway if there is any I haven't found it yet. So PB in Nortfolk NE told me what they do is insert a relay by the firewall and that's where I'm at. If you perhaps could direct me to finding the currant location of an excisting relay or how to freshly build in some .