I forgot to make mention of when the multi meter is taking the Amp reading it starts at the higher number and then begins to drop lower the longer it is hooked up.

I have no idea what this may indicate, maybe a short somewhere down line? But then I am taking an uneducated guess.....

 

Sorry, another question if I may.

When I test the wires at the brake, do I disconnect both wire and use the multi meter attached to both the + and the - wires. Or do I cut one of the wires and attach the meter leads to the two ends of the cut wire?

I just want to do it correctly.

 

not sure of all that but you should get 3 amps at each wheel. I would think you can test the hot side of each wheel without cutting any wires. if you have a clamp style meter.

 

Clamp meter is out, I am back to the old school probe end meter. Which does kind of for a better choice of words..Sucks. They don't give much extra flex in the wires when they run them for the brakes. Kind of like Ford and their generous 3" up-fitter lead wires.

 

Lots of questions. First of all 10 amps is less than I would expect to see through the break-away. If that reading is accurate it is too low.

Do not cut any wires. Just carefully inspect the connections at the wheels. It sounds to me like there is a poor connection somewhere down the line. Use your probe and check voltage at each magnet. I would advise against cutting wires.

Steve

 

Are you running off the break away battery? Yes, it will continue to drop in power as it looses charge from using it. Those batteries are not very big and not meant to last more then a minute or two before dropping voltage.

 

It was my understanding that on the 5th wheel, the 12V RV battery which is a large deep cycle batter, is what the break away switch is wired to.

Am I mistaken?

 

no, you are correct.

steve

 

Ok. That make sense. My Haulmark uses a small battery even though it came with a battery for the original interior lights.

It should not see a big drop unless it is an older battery. 10 amp should not draw a good battery down that fast.

 

The battery is only 2 months old. The old battery was still good, I'm just **** about some things.

 

UPdate: Haven't been able to get out to do anything on the RV today as I have the grandsons under feet.

Thanks for understanding,

 

OK, here is what I have new to share.

Battery is putting out 12.91-12.92 V
Break away switch shows 12.81-12.82 V
Break away switch shows 10.0310.08 A However the amps do begin to drop the longer the switch is active.

Front passenger side brake shows 8.84V and 1A
Rear passenger side brake shows 8.16V and 1A
These readings were taken by probing the wires just ahead of the magnet. The wires are concealed into the magnet.

The rear wheel magnet did have a fair amount of grease or grime on it as did the inside of the brake drum. Not full blown seal grease but enough to be visible. This drum and magnet were cleaned before assembly.

All four brakes were adjusted to the proper settings of backing them off after they started to drag while turning the tire and wheel.

If I pulled the break away switch I could feel the brakes activate, but not stop the truck from rolling.

If I applied the manual switch in the truck I could feel the brakes slow the truck, but again not stop the truck.

We did not get to the passenger side trailer brakes as time ran out.

Question, what would cause the amps to drop the longer that the break away switch was active? Could this be a sign of a chaffed wire grounding out?

We did inspect all the wiring that is visible on the system from where it exits under the truck and is then wired to each brake. We found no worn nor chaffed wires.

 

Resistant goes up as things heat up with the passage of current.

Amps = voltage/resistance

Voltage is fixed, resistance goes up, amperage drops. Amperage is the highest at first than drops off over time.

Steve

 

If all the connections are good and your amp draw is consistently low to all wheels, about the only thing I can think of is to clean up the ground for the brakes. Your voltage is good so there is nothing left I can think of.

Steve

 

Not to sound stupid, but where would I find the ground for the brakes? Would the ground be back in the wires located in the junction box located near the hitch pin? Or would there be an actual ground point on the trailer frame to look for.

Last question if I may, I had read a story about a gentleman who lost is trailer brakes. It turned out to be that the wires had chaffed inside of the axles where they had been run from the factory. Could this possibly be worth looking into give the symptoms I have?

I do greatly appreciate your help and assistance. It is people like you who set the high standard that we all should strive to achieve as members helping members.

Thank you,
Jon