Weird Electrical Issue/ Need experience of RV.net

[Shacklaw]

If you recall the scene from Indiana Jones where he looks into the pit and says "SNAKES, it had to be snakes"...that's me right now.

I'll try to condense-I've had this poor ol' coach for years. Last time I actually used it as a coach, I was having an issue of draining batteries and a small "shock" from the frame if you were sweaty and touched it, but it was manageable. It thereafter became the building office for our house, was taken to the lake to be the building office for the lakehouse, was brought back home and allowed to sit for a couple of years. About 5 years total. I have now decided to restore it.

I attempted to start it. No go. Fresh battery, jump box, nothing.
Changed starter. Rolled over several times, spuddered. Nada.
Check the battery drain with multimeter on amps on negative post,
23.4 amp draw with everything off. It would go to 34, then down to 10.5, then 0, then back up. Never stayed constant.

I isolated the chassis side from the coach side (as far as I can tell) Coach Batteries out, bird disconnected, etc.

All that is left is: Power cable from chassis battery to on/off solenoid, (power equal on both sides), cable to bird, bird to starter. If you don't connect the 2 cables at the bird (battery and starter) no power loss. As soon as you hook the 2 cables together (that's their normal config.) you get a 23.4 amp draw. Alternator completely disconnected. Seems to be from the cable to starter.

New Starter (same results with old, so it was good) a main cable to the solenoid, a small wire to the start pole, and a light purple heavy wire from the main cable lug up into the loom towards the dash. Best I can tell that's ALL that's hooked to the battery.

I'm stumped!!!! The light purple wire goes somewhere. I see it go into the loom, but I have yet to find it on the other side. Does it go to the ignition switch? Fuse panel? Where?

This is a lot of draw for NO FUSES being blown. I've check all fuses under the hood, nada. Out of ideas on where to look. Ignition switch? Fuel pump? What could draw that much amperage and not be easy to find? IDEAS?

[enblethen]

Fuel pump relay is under the dog house. It is on the left side chassis brace about middle of dog house opening.
You could be correct that the converter does not charge chassis battery. My battery control center does not have the small circuit board that plugs into the fuse panel in the battery control center to enable charing chassis battery. Common for our era not to have charge circuit.
Doubt that is problem! You should be able to hear pump running. It only operates when ignition is on and EMC sends signal for about 10 seconds to relay.
I would start pulling fuse to locate load. Start by using battery disconnect to shut down Fleetwood items that operate through the battery control center.

[Shacklaw]

I appreciate all the input.
Joe, I believe it is right. It's a Fluke, moved red to "10a fused", turned switch all the way around to last setting (DC Amp) and placed one lead on battery and one lead on ground cable and got 23.4. Move it all to mA and got 234. Went this morning, hooked it all up and got 18.2 pretty steady. Am I hooking it up right and why isn't it blowing the internal fuse of the meter?

I believe it's isolated. My belief is the Converter charges the Coach batteries, not the chassis. IF you need a bump on the Chassis, you have the button to connect them. Is it possible there is a crossover between coach and chassis at the converter?

Last, my parts guy suggested that a "stuck" fuel pump or faulty relay might cause a draw like that through an internal dead short. What do yall think?

WHERE IN THE HECK IS THE FUEL PUMP RELAY ON 1991 A P-30 FLEETWOOD??? no one has definitive answer.

Thanks!

[Joe417]

I'm asking basic BE&E questions and not trying to insult as you may know perfectly well how to use the meter, but are you sure you are using you multimeter correctly.

You said "Check the battery drain with multimeter on amps on negative post 23.4 amp draw with everything off". Did you mean with multimeter between the cable and negative post.

You have to disconnect the cable and connect the meter in series with the load to measure current. Not parallel.

Another thought,

Most average multimeters have a mA range and a 10A range and require the user to move the leads to the correct input for the range chosen.

Could that measurement have been 23.4mA. As someone else said, 25A is a large draw on the battery with nothing turned on.

[Germania]

With that kind of amperage draw the problem area has got to be at least warm to the touch, probably hot.run your fingers around the area and see what you find.
I agree with prev poster 23 amps is usually not measurable unless you have clamp on meter.What kind of arc do you draw when disconnecting suspect wiring, at 23 amps should be a substantial splash.

[enblethen]

What chassis?
GM feeds to the starter and to the battery control center. The battery control center feeds through the battery disconnect then to chassis items.
Fords feed to a starter relay with fuse links feeding chassis items.
When you turn on the key to on, does the dash light up?
When you go to start do you hear a good click?
There should not be a big drain as you indicated. I would diconnect the large post on the alternator to see if it goes away.

[turbojimmy]

westend wrote:

turbojimmy wrote:

westend wrote:
One thing that will draw that much current is a partly shorted wire or device. The BIRD would be high on my list of suspects.

Someone throw me a bone. What's BIRD?

BIdirectional Relay Device

Thanks!

[westend]

turbojimmy wrote:

westend wrote:
One thing that will draw that much current is a partly shorted wire or device. The BIRD would be high on my list of suspects.

Someone throw me a bone. What's BIRD?

BIdirectional Relay Device

[turbojimmy]

westend wrote:
One thing that will draw that much current is a partly shorted wire or device. The BIRD would be high on my list of suspects.

Someone throw me a bone. What's BIRD?

EDIT: I looked it up. If the BIRD is still in play, then the house isn't completely isolated. I'd get to a point where you have nothing but chassis hooked up to a known good battery.

[westend]

One thing that will draw that much current is a partly shorted wire or device. The BIRD would be high on my list of suspects.

[turbojimmy]

Shacklaw wrote:
This is a lot of draw for NO FUSES being blown. I've check all fuses under the hood, nada. Out of ideas on where to look. Ignition switch? Fuel pump? What could draw that much amperage and not be easy to find? IDEAS?

That's a big draw. I would guess that there aren't many circuits protected with fuses bigger then 20A. Unless that mysterious purple wire is really big I doubt it's carrying that current.

So where does that leave you? I don't know. What do you mean by "bird"? Are you sure the house is completely isolated? I can't think of anything on the chassis side that would draw that much. Maybe a blower motor would approach that, or old school exterior lighting. How old is the battery?

[Artum_Snowbird]

In almost forty years of being an electrician, unless you have a clip on ammeter, I don't think I have ever seen a multimeter than can measure that kind of amperage.

If you have a set of jumper cables, connect the negative on the battery to a negative near the starter. If it works, you know you have to look at the negative side of things.
If it doesn't work, take off the negative jumper and connect the positive battery post to the positive start lead on the starter. If it works, you know you have to look at the positive feed.