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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3131
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 have 2005 century and LVD is not working 't have any

Customer Question

Hello I have 2005 century and LVD is not working don't have any lights or charger inside when I jump the ISO and ACC in fuse panel they work but I tried to by pass the LVD by bolting two hard wires on LVD together it doesn't work only works when I jump ISO and ACC what you think is wrong
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 1 year ago.

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

What are you referring to with LVD?

Customer: replied 1 year ago.
Low Voltage disconnect
Customer: replied 1 year ago.
when I jump ISO and ACC in the fuse panel the lights and chargers start working but if bolt the two hard wires on Low voltage disconnect switch(box behind the trash can it and disconnect the jump between ISO and ACC nothing works
Customer: replied 1 year ago.
It's the same problem as in this link
Customer: replied 1 year ago.
I tried to jump ISO and ACC it worked but not the second where I can bypass the LVD is there any fuse that might be blown I chkd all the fuses and they looked ok
Expert:  Jeremy replied 1 year ago.

I gotcha.

You can rule the LVD out and go to the wires themselves. Doing the bypass like the link you provided was to rule one of the 2 out. You ruled out the LVD so now the wires need to be chased to see where the bad connection is creating the issue.

Check the ohms between the LVD wire and the ACC post in the fuse box to see that you have less that .1 ohms. If not, the issue is on that side. If good, then the issue is between the LVD and the starter.

You want a 5 star service and I want to provide a 5 star service. Please consider that I don't know your skill level as well as I can't see,
touch, smell, hear the vehicle/machine in question. Please provide as much detail as possible and I will provide as much back.

Once an answer is provided, you should see a rating screen. Please rate my personal service to you. The ratings are my personal feedback,
they are not the site feedback.

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Customer: replied 1 year ago.
How do I check the wire between LVD and started.
Expert:  Jeremy replied 1 year ago.

Check to see that you have a full 12 volts, then either check the amps or ohm test it with a Power Probe. You need to see at least 50 amps with a amp clamp.

Customer: replied 1 year ago.
I will check tomorow and let u know
Customer: replied 1 year ago.
You mean 12volts at LVD volt in wire??
Expert:  Jeremy replied 1 year ago.

Correct. I'm presuming it was checked, but the amps is what also needs to be checked. There may not be enough amps going through to have the relays activate on the pins from it. Jumping them bypasses the LVD for you have one source from the LVD and one source straight from the post.

Do you have the VIN so I can pull up the electrical manual for you? I need the full VIN for my setup with Daimler.

Customer: replied 1 year ago.
U20764 are the last six if that works. Just wanted to check if there is any fuse that might have blown. Incase there is any fuse that is not directly visible....just wondering....
Expert:  Jeremy replied 1 year ago.

CLICK HERE for the electrical schematics manual. This will have the wiring in how the whole system is setup.

Expert:  Jeremy replied 1 year ago.

You get my manual and you run? I am closing the link since I paid for the link.

Have a good day.

Customer: replied 1 year ago.
Sorry Jeremy but the manual was of no help had to chk with with my mech to get it done.
Expert:  Jeremy replied 1 year ago.

Good day.

Expert:  Jeremy replied 1 year ago.

You asked for a refund, so I closed the link.

Have a good day.

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