No power to my fuses

[lathe11]

Started my coach to bring it in for tires, no backup camera, ok fix it when I get home, Well, now the problem. Pulled the fuse panel found the fuse and it was good but no power to it, tried the fog fans, same thing driving lights you got it. All the fuse are good but not getting power to this same row, where do I look next to find the feed to the fuse block? Swapped the relays, checked the fuses at the batteries all check out fine , I am stumped, any help would be appreciated! Oh, coachman sportcoach,DP, 380.

[Sprig]

enblethen wrote:
Put one side of test light or meter to ground, touch each side of fuse with other lead.

The OP Title is "NO POWER TO MY FUSES".

OP wrote:
All the fuse are good but not getting power to this same row, where do I look next to find the feed to the fuse block?

Well, ... at the least ... the story seems ... inconsistent.

With the new manufacturing techniques today, I would not even bother trying to use a meter and securing leads to find the problem.

All the fuses I have ever seen, for a typical American vehicle, all have fuses that comply with electrical code so that can be visually inspected to determine if they are "blown".

[enblethen]

Put one side of test light or meter to ground, touch each side of fuse with other lead.

[Sprig]

lathe11 wrote:
...Word of advise check both sides of the fuse!!...

How do you check "both sides" of a fuse? Can you provide more detail?

[lathe11]

Well after going thru all the line and fuse checking I finally got it!! Word of advise check both sides of the fuse!! I know better but you get in a hurry and it cost me 8 hrs. of aggravation! Thanks for your help and suggestions!! Now I have to keep a eye out for what made it blow, my guest is the compressor motor for the air horns, the pressure switch is not kicking it off at 120-130 psi, for now it is unplugged!!

[iceyfingers]

I found this on u-tube but get a single strand of copper wire about 2 inches long and wrap it around each of the metal contacts of the relay. when you plug the relay in you can see what each circuit is doing in the relay.google testing a relay.

[lathe11]

I'II give it a try. The coach starts, but just not getting power to a row of fuses, This is on a Frieghtliner chas, DP.

[enblethen]

There is normally only one power source to the igntion switch. If the engine turns over then No, the fuse would be after the igntion switch. If the engine does not turn over then yes, the fuse is before. On many GM products, there is a fuse link that supplies power to the igntion switch via the main fuse block "Hot all the time" portion. There is a fuse marked "IGN" that feeds the ignition switch.
You can manual use a jumper between a known hot power location and touch the ignition switch side of the realy coil. I have a test jumper with a fuse installed. That way if I touch something wqrong the fuse will blow rather than the wire melting down. This can be done using chassis battery, coach battery or power off the converter.

[lathe11]

enblethen,why would they have a fuse before the fuse panel? Also how can I check the relay while plugged in? Is there a way of checking them when they are unplugged? Thanks

[enblethen]

Relays vary on configuration. Each has a coil that needs to have conituity checked. There should be resistance on the coils.
Check the circuit to see if one side of the coil goes to ground.
The other side of the coil should have 12 volts DC when the ignition switch is in the "ON" position.
Contacts can be checked when the coil is energized.
I would start by tracing the power from the ignition switch toward the relays. I am betting on a blown fuse in the control circuit.

[lathe11]

Thanks all, yes I have power to the panel, it is the two row of fuses that are energized by the ignition. I see the three big relays and have interchanged them and got nothing, there are two rows of relays at the bottom of the panel but none are labeled and there is no diagram. I believe that is where my problem lies ,but how do I check the relays??

[sch911]

Coach battery disconnect engaged?

[enblethen]

Should add that many DPs have relays and fuses in external compartment below the driver's seat area. The relay could be powered by a fused circuit off the ignition switch. Type of relay will vary so you will need to look at the schematic that normally is in compartment.

[crasster]

check power going to the fuse panel first... So are you getting any 12v?

[enblethen]

Those items could be powered from the ignition relay in your battery control center. The relay may not be energizing.