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deandec · 07-20-2021, 01:14 PM

The 20A ignition switched fuse slot for my Dash AC Compressor Clutch does not pass electricity.

I need to move the Compressor Clutch wire to an empty 20A fused slot on my Chassis Fuse Board.

The board has no empty Ignition Switched fuse slots to use for the replacement.

If I move the Ignition Switched wiring to an Always On fuse location, what negatives will I encounter?

Boogie_ · 07-20-2021, 07:43 PM

If I'm understanding your problem correctly, here's a couple things I would try depending on how the wiring and fuse box are set up.

Wire in an in-line fuse holder.

Use an Add-A-Circuit Fuse Tap on a low priority fuse slot.

Add an auxiliary fuse box.

Hope this helps.

deandec · 07-21-2021, 02:02 PM

Thank you for the suggestions.

I may not understand them clearly but they all seem to be non-switched solutions.

As I mentioned I do have a 20A empty fuse position to use that is non-switched by the ignition.

My question is will using a non-switched fuse for the AC Compressor Clutch cause any problems?

Country Coach likely had a reason to assign this fuse to the ignition switched group.

Of course the Compressor Clutch is also switched at the Dash AC Controls and at the Dryer (if the 134a is low). So I am hoping to learn the purpose of assigning the Compressor Clutch to wiring that is controlled by the ignition switch.

CRV2 · 07-21-2021, 02:06 PM

Quote:

Originally Posted by deandec

Thank you for the suggestions.

I may not understand them clearly but they all seem to be non-switched solutions.

As I mentioned I do have a 20A empty fuse position to use that is non-switched by the ignition.

My question is will using a non-switched fuse for the AC Compressor Clutch cause any problems?

Country Coach likely had a reason to assign this fuse to the ignition switched group.

Of course the Compressor Clutch is also switched at the Dash AC Controls and at the Dryer (if the 134a is low). So I am hoping to learn the purpose of assigning the Compressor Clutch to wiring that is controlled by the ignition switch.

A lot of people leave their A/C on and just turn off the engine whenever parked, if the A/C clutch was wired to an always on circuit and the A/C was on, it would run down your battery(s) even though you have turned off the key and engine. ~CA

YC1 · 07-21-2021, 02:12 PM

Not a good idea Dean. Constant current draw that could possibly damage a clutch that gets no air circulation when not in operation.

If the bad slot still has the ignition control but the fuse panel is sick you could potentially use that ignition control to power a simple Bosh relay and feed that relay with the 20A circuit that is still viable.

Have you pulled the fuse panel apart/off the mount. You might be able to do some slot swapping of parts from the back.

But no, I would not supply constant power.

amosnandy · 07-21-2021, 02:25 PM

Quote:

Originally Posted by deandec

The 20A ignition switched fuse slot for my Dash AC Compressor Clutch does not pass electricity.

I need to move the Compressor Clutch wire to an empty 20A fused slot on my Chassis Fuse Board.

The board has no empty Ignition Switched fuse slots to use for the replacement.

If I move the Ignition Switched wiring to an Always On fuse location, what negatives will I encounter?

If you wire to a fuse slot that is always hot, or even for that matter one that is hot with the ignition in the ACC position, if you do not turn off the heat/cool switch completely the ac clutch will always be on. Two things can happen. First, you will run your batteries down. Second you may burn out the AC clutch. If it has power to it and is not turning, the clutch is engaged in a standing position. The clutch is basically a magnet, and you would burn it out.

You don't say why the fuse slot does not pass power. Is there power coming in, usually the top, but not going out the bottom? even with a good fuse? If it was mine, I would pull the fuse block loose. Usually 4 screws in the corners. Hopefully you can get at the back of it and see why it's not passing power. The most likely is the wire has broken or burnt on the input side of the fuse slot. You can actually pull the fuse connectors out of a fuse box and replace them. If it is a burnt or broken wire, you take the fuse holder from the bad point, put a new receptacle on it and push it back into the fuse block. It takes a special tool or very small screw driver to get them out without damaging them but since this one is bad I wouldn't worry to much. The alternative is to snip the hot wire going into the fuse block, put an inline fuse, snip the bottom wire and connect it. Just remember to mark it with tape and marker so the next guy knows what it is for. You can buy inline fuse holders at any auto parts store, or if you want to swing buy Minnesota I have a bunch in my spare parts drawers in the side cab.

deandec · 07-21-2021, 07:42 PM

Thank you to all for the explanation of why the Clutch is powered with the ignition switch. Yep, I have not turned off the AC dash control on many occasions after shutting down the engine.

Here is a picture of my Chassis Fuse setup.

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3 Vertical Rows of 12 fuse positions each

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20A fuse at bottom of center row does not work. Wires 208 & 96c

I measure -11.82 dcv across that bottom fuse. Plus the indicator light, does not illuminate.

The 20A fuse has continuity.

The Center Row of 12 fuses is switched on by the Ignition Switch.

The Ignition relay is grounded to the negative post of the failed fuse socket.

The engine starts instantly.

I think dismantling this center row is no small task, so am looking for an alternative approach with my original post.

spinroch · 07-21-2021, 08:47 PM

Deandec: Are you sure that the black wire at the bottom left of the center row is not +12V with the ignition switch ON? It looks like the feed is on the left and the load connects on the right. If this is the case, and the fuse holder has failed internally, you can connect a pigtail fuse to the left Buss and connect the other side to the screw that holds wire 208 & 96C.

deandec · 07-21-2021, 09:14 PM

Quote:

Originally Posted by spinroch

Deandec: Are you sure that the black wire at the bottom left of the center row is not +12V with the ignition switch ON? It looks like the feed is on the left and the load connects on the right. If this is the case, and the fuse holder has failed internally, you can connect a pigtail fuse to the left Buss and connect the other side to the screw that holds wire 208 & 96C.

Wow! Great Question. Thank you!

No, I am not sure, I just "assumed" that the red wire was the power with my twisted thinking.

Since the manual says wire 96c runs "from the fuse to the AC Clutch Relay", I would think you are correct.

The fuses just serve to interrupt the voltage flow? There is no negative connection on the fuse block.

I will install the pigtail tomorrow provide the feedback.

dabrooks · 07-22-2021, 04:59 AM

Maybe it's just me but that black wire looks burnt.

spinroch · 07-22-2021, 06:03 AM

I believe there is a negative lead at the top of the Buss bar. (The white lead). This would be needed for the LEDs to light up.

The fuses are to protect from over current flow. Too much current can cause damage & fires.

It's like water in a pipe:
Current flows through the wire, like water through a pipe.

Voltage is like water behind a dam. Voltage is the potential energy, like the pressure on the dam wall.

You need a 12 volt test light and a cheap multimeter. The Harbor freight ones are a good place to start. Everyone has their own opinion about this. I have many types of multimeters... the cheap ones I use in the car & RV. If you break them, you can toss them and get another one. You can learn how to use them on YouTube.

Try temporarily connecting the IN and the OUT sides of this circuit at the Buss bar with an equivalent pigtail fuse available at any auto parts store. This will tell you if your suspicions are correct.

YC1 · 07-22-2021, 08:04 AM

Take that large wire off, cut it back and put a new connector on it. Clean the post until it is shiny. A tiny wire brush on a dremel tool works a treat.

I think you have an IR drop. That is, a bad connection and you are losing it.
As suggested, you can jumper it but you already know you are not getting the voltage.

Always fix the obvious first. That is, if you see something that does not look right, fix that and often other issues will clear up.

wolfe10 · 07-22-2021, 08:15 AM

Though it appears there is a good solution here, there IS another option where you want to draw 20 amps from a "always hot" source, yet only have it supplying a device with the ignition on.

Use a RELAY-- oversized for your current/amp draw. So, for a 20 amp fuse, I would use a 40 amp relay.

Always hot source wired from its fuse to the IN of the relay.

Ignition source (tiny draw-- just to close the relay) T'ed in from any ignition hot source for closing/opening the relay contacts.

Other relay connections to ground and OUT to device being powered.

Have done this often with headlights that are only seeing reduced voltage and therefore DIM. Here the head light switch only closes the relay and power to the headlights through the relay from large gauge wire (with fuse) from the chassis battery or large-gauge wire from chassis battery.

YC1 · 07-22-2021, 09:56 AM

With the fuse out, use a burnishing tool/points file to clean the connectors. I know, no one has one of these anymore. A piece of sandpaper folder in half with some glue in between can be used.

Then use a tool to try and spring the contacts closes a bit. If that does not work. Bend the fuse blades a bit off center and see if they make better contact.

Not the perfect solution of course but might help you diagnose the issue.