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fishingjohn · 04-12-2012, 02:38 PM

I was changing the plugs and wires on my motorhome when I pulled the coil wire the wire going to the small round thing under the coil sparked. I had the key switch on my stupid self. Now motorhome will not crank. It turns over fine but it is not getting any spark. When the wire sparked what could I have damaged. I don't have a test lite but I have volt meter.

subford · 04-12-2012, 03:57 PM

That wire comes from the Ignition Switch and if it is a 94 F53 you now have a bad 20 Amp fuse, fuse "V" in the engine compartment fuse box in front of the radiator.

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fishingjohn · 04-13-2012, 07:06 PM

I checked fuse and it was good . I went and bought a 12 volt light tester and fuse was good . I hooked it up to the wire that sparked and no juice to the wire. the wire i'm talking about comes out of the plug that goes to the coil and goes to the small round condenser.

fishingjohn · 04-13-2012, 07:10 PM

thanks Subford for all the help. If you know any thing else I can check it would be appreciated. Money is tight after purchasing the motorhome so I got to do all the work myself.

subford · 04-13-2012, 07:40 PM

Well if is not fuse V then it would be fuse N or a bad wire or Ignition Switch (not the key tumbler).

By the way that is not a condenser, it is a Radio Capacitor.
The term condenser was last used about 1925. That is when they found out that it did not condense electricity away, it stored it or had a capacity for it.
I only say this because that is what it is called in the Ford diagram below.

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fishingjohn · 04-13-2012, 08:01 PM

where is the ignition switch located ? And what does it look like.

subford · 04-14-2012, 05:31 AM

Recheck those two fuses (V & N), I bet it is one of them.

Quote:

Originally Posted by fishingjohn

where is the ignition switch located ? And what does it look like.

It is located low on the steering column.

Bottom of steering column (A7) in the diagram below.

Ignition Switch:

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fishingjohn · 04-14-2012, 11:08 AM

Ok I have power with the key switch on to the coil both wires going into coil the white one and the red one light up the tester. But I still do not have spark from the coil. I replaced the coil with a junk yard one still no spark. Do you think it is the coil or something else.

subford · 04-14-2012, 12:34 PM

Does the fuel pump run for one second when you turn on the key and then stop running or does it run all the time the key is on with the engine not running?

fishingjohn · 04-14-2012, 01:02 PM

it runs all the time

fishingjohn · 04-14-2012, 01:04 PM

i wondering it started out as a fuel pump issue fixed it now no spark could these be related.

subford · 04-14-2012, 01:17 PM

Quote:

Originally Posted by fishingjohn

i wondering it started out as a fuel pump issue fixed it now no spark could these be related.

Yes.
Unplug the PCM Computer and see if spark returns.
If you have spark with the PCM unplugged and no spark with it plugged in you have more than likely a bad PCM Computer.
In other words the clock is not running in the computer. It either has bad Electrolytic Capacitors (leaking) or a bad crystal in it.
The clock has to run to ground the injectors also so the injectors are not firing either.

The only other thing it can be is no power to pins 1, 37 & 57 or no ground on pins 40 & 60 of the computer. Not likely with the fuel pumps running with the engine not running.

Some have replaced the Electrolytic Capacitors or the crystal at board level to get the Computer working again. You can do this if you are good working with electronics.