Does anyone know how to jump these relays?

[coolkx]

Hi All,


This is for a 1993 FleetWood Pace Arrow 37J W/ Ford 460 7.5L

When I first acquired my motorhome it had absolutely no power. When I turned the key on with new batteries or on a charger, nothing would happen. Someone proposed I should try and jump the relays to see if I could get power. Well, it worked, in a way. It supplied power, I can't figure out which leads are supposed to have a hot connection and ground.

On modern day relays, the little body schematic is really helpful to know when you've closed the circuit, but on these old things, I have no clue what I am doing.

Does anyone have a wiring diagram for this, or know of anyway to test the relays?

When I "jump" them, I place a wire on a positive and negative terminal of a battery and directly onto the to center leads on these relays, I hear a click, but how do I know they aren't reversed?

Is there an empirical method on determining which ones are faulty and which are sound?

[okcnewbie]

You could take a battery and apply voltage to one coil at a time. Then check with a meter for a short.

[YC1]

I assume you have removed the little wires before applying your own power?

If not, you could get a hand full of hot wires.

Assuming you did, the polarity does not matter. These are very simple electromagnets. A coil of wire wrapped around some metal. When current passes through, the magnet activates. The magnet pulls a metal bar down and shorts the large connectors together.

Once the relay is activated the large posts should be a dead short. That is, any voltage on one side should be exactly the same on the other side. Think of it as putting a screwdriver directly across the large terminals or just bolting them together.

[beaverfever]

are you aware of the "salesman switch" over the door that kills all power?
also there is house batteries and chassis (engine) battery?

[okcnewbie]

Here is what I've come up with so far. See attached diagrams.

K1 ties your batteries together. Probably with the Aux start switch.

F1,2 should be a short at all times unless tripped. They look like they auto reset but there may be a reset switch on the side.

You can bypass K1,3 if you want to start the genset.

You can bypass K2,4 if you want to start the Engine.

[NHRA225]

Originally Posted by beaverfever

are you aware of the "salesman switch" over the door that kills all power?
also there is house batteries and chassis (engine) battery?

I would be very cautious about jumping any of those Solenoids !
Call Fleetwood and ask them for advice , I'm sure there is a remote Panel disconnect Switch somewhere in your Coach that is turned off.

[okcnewbie]

Originally Posted by NHRA225

I would be very cautious about jumping any of those Solenoids !.....
.

I agree! Don't short the positive to ground. Otherwise you should be ok. It's a very simple circuit that includes four switches. In most coach's the positive of the chassis and the house batteries are connected at times. This is ok.

[NMRVer]

When you say " no power" what are you trying to say. Do you have power to energize the relays? No 12V anyplace? What happens when connected to shore? More info would be helpful..

[wa8yxm]

On those solenoids you have 4 connections, Two are BIG and I mean BIG and two are Small

To jump wither move one big wire to the other big terminal and connect or jumper the two BIG terminals together.. Leave the little wires alone.

[Timay]

Which is gonna be worse - the $100 service call or the many hundred dollar repair from jumping the wrong terminals - just for a second?

You have gotten some good answers, but it is too easy to blow things if you don't know what you are doing.

IMHO

Tim

[NHRA225]

We'll said Tim !



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[coolkx]

Originally Posted by Timay

Which is gonna be worse - the $100 service call or the many hundred dollar repair from jumping the wrong terminals - just for a second?

You have gotten some good answers, but it is too easy to blow things if you don't know what you are doing.

IMHO

Tim

I think I have blown things already, lol. Grr. I am so inept in this department.

[chboone]

coolkx
The lower black/gray solenoid is for the chassis, says on the label COACH CHASSIS, it is has to be closed to power the chassis and start the enigine. You can tell by the large cables on each side. The upper black/gray is for the house 12V power. It needs to be closed to supply power to every thing in the house that requires 12V+ to operate. Both those solenoids are latching solenoids they stay closed or open without having power supplied to the small terminals all the time. To energize the house or chassis the rocker switch for either one is pushed and 12V+ is supplied to one of the small terminals and the other small terminal is grounded to close the contacts. To kill the power the switch is pushed again but in the opposite direction 12V+ is supplied to the opposite terminal then before and the other terminal is grounded. You should hear the clunk each time the switch is pushed. The only time 12V+ is supplied the either terminal is when the switch is pushed. The other two shiny metal solenoids are non latching and have to have 12V+ supplied to one of the small terminals to keep the contact closed. The other small terminal is always grounded, they do not switch polarity as the latching solenoids do. While they look like the old Ford starter solenoids they are not. They must be CONTINUOUS DUTY a starter relay is not continuous duty and will burn out if used for a continuous duty application.

[YC1]

http://www.metrotrekkers.org/utility/electrical.htm

This site is a fun way to learn about these systems. Don't worry that it may not match your setup exactly. It will give you a good visualization of how things can work.