Hello Forum-Folk...
I have a 1989 E350 based Motorhome with a 7.5L Gas engine.
When it's "Parked" for the Winter, I run the engine once a month for an hour.
Today, I ran the engine, and tried to turn on the heat (it's a bit chilly up here in Ontario). The blower wouldn't run.
I had a look at the fuse box under the steering wheel - noted that there are a few missing fuses.
Checked over the fuses and nothing was blown.
Took a spare fuse and inserted into two of the emty spots - no blower.
Turned-off the engine, and as I moved the keys, the blower started.
So I figure I need to replace / clean the ignition switch.
Went to turn the engine back on - no go: Check engine light, "Click" noise, but the starter will not run.
I guess I must have fried something when I put the fuse in the empty spot. Live and learn - won't do that again.
Both the Starter and House batteries are good - 12.9v.

So now I need to get the engine running.
I checked all the fuses in the box under the steering wheel - nothing blown.
I looked to try to find the Power Distribution Box under the hood. Cannot see it.
Took out the Starter battery (LH side of engine compartment) - can't see it under there.
Looked around the House battery (RH side of engine compartment) - can't see it around there.

Figured I would start by looking at the fuses in the Power Distribution Box, then relays, then...

Can anyone help me to find the Power Distribution Box?
Anyone know what I might have fried?

Hope this lesson isn't too expensive~!

Thanks!

 

It might help if you posted the year of the RV.
Mine is not a 7.5, but the power distribution box on the 1994, 5.8 is under the master cylinder.
Its kinda hard to see in the pic, if its there.
Since its a motorhome it could be in a very different location but I would think it would be near one
of the batteries.

 

Great point - It's a 1989...

I couldn't see it anywhere around the batteries, but that doesn't mean it's not there~!

Thanks for the response.

 

I don't think my 88 E150 has a power distribution box. There is the fuse block and everything else is going to be fuse links.
Ignition switches do go bad... You may have a bad one.

From my 1988 EVTM

Power Distribution
The Alternator and Battery are connected together at the Starter Relay hot terminal. Other circuits originate at the Starter Relay hot terminal and are protected by fuse links. Low power circuits are also protected by fuses.
The Ignition Switch and Light Switch are powered at all times, as are Fuses 1, 4, 8, 10, 12, and 16. The other fuses are powered through the Ignition Switch or the Light Switch.

 

What about the blower resistor?

Does the blower run in any other speed setting?

 

Before you go deep with the ignition switch ( and in the end it could eventually turn out the problem) but check for and clean corrosion off all the circuits. I too have a 1989 E 350 motorhome with 7.5, and that has been an issue for years.
I am not sure what you mean by a power distribution box; you have found the fuse panel inside, and as has been pointed out , the power goes from the positive side of the battery on the passengers side of the truck to the starter relay; from there it is tied into the main harness that powers the truck. clean those terminals and all the wiring associated with it.
Also look closely at the battery terminals themselves; they have been replaced those are not original, but a quickie universal replacement. Those get you out of a jam, but are very succeptable to corrosion on the wires. Undo the bolts and check the wires, see if there is a build up of corrosion in the wires or the terminals themselves.
If after this is done and you still have issues, then time to dig deeper into troubleshooting the ignition switch/starting circuit. Good luck

 

Maltondhc and MoDaMaster are correct. The blower motor circuit comes from a fused link which comes from the starter relay. bad connections and you could loose the blower and starting..
You should have a blower motor relay. The relay is switched from your Heat/AC control panel but the power through the relay contacts to the blower motor comes from a fused link. The blower motor resistor can go bad or the connections to it.

You said "Check engine light, "Click" noise, but the starter will not run." By Click noise, you mean when you turn the ignition switch to the start/crank position, you hear the click from the starter relay? You can use a volt meter on the starter side of the relay and have someone turn the ignition switch to the start position and see if you are getting power through the relay to the starter cable.


Here is a diagram that might help with the heater side if it turns out that you have a problem in the heater circuit.

 

Thank you all for the info. I think this is going to help me quite a bit in figuring out what I have done...

Battery post connectors seems to be good, but I will check shortly to confirm.
Blower IS running. Issue with the blower was something in the ignition/key swtich.. When I moved it, the blower started, and now runs fine. I'm sure that will need work at some-point~!

I think this sounds like what I need to do: You can use a volt meter on the starter side of the relay and have someone turn the ignition switch to the start position and see if you are getting power through the relay to the starter cable.

If the fused link protects both the Starter Relay and the Blower, and the Blower works, perhaps I killed the Relay, but not the Fusable Link... I'll have to figure out what the Relay looks like and test continuance. Most of my previous experience has been on motorcycles, so this is a learning curve for sure...

It's -12C today, so I won't be digging into this today... TOO COLD! I'll let you kind folks know what I find out.

If anyone has a photo of what a Fuseable Link looks like, it might help me~!

Thank you!