Update on ZF trouble 87FC35

[Gregory OConnor]

Why find it. find a good hot lug and use a ignition wire to open a
new relay to power the ECU. find out the amp limit and fuse it. Make
a note on #19 of the change you made. You may have to power the
relay that cuts off the starter solenoid as we now know that the
starter solenoid wont power at all without power to the ecu. I know
it sounds like ducttape and bailing wire advice but if you replace
the relay supplying the power you may only be repairing a result and
not a cause. It just sounds to me that fixing your failure will not
correct the problem.

I dont like to reengineere things. In my field of expertiese, I use a
hammer. When that hammer wont complete the task, I get a bigger
one. I think you need the expert advice of JohnF, TomW, CurtS JeffM
and the other electrical members. This ZF power thing is gonna get
some one hurt. It would be great to do an upgrade to a bus and keep
it from developing the "ZF'up"

Gregory O'Connor
94ptRomolandCa


--- In WanderlodgeForum@yahoogroups.com, "Alan"
wrote:
>
> One more thought. I re-looked at the "fix" on the web site for a
> low-voltage problem. I don't think i've ever found that 12 volt
> relay for the ZF. I found the 75amp one, but this appears to be
> another one. ZF wire #19 is nearly impossible to trace. best i
can
> tell, it goes under the coach and off into oblivion. ...But my
> common sense tells me I'm missing that relay and it's probably
> someplace accessible, I just don't know which one it is. ANY IDEAS
> ON WHERE THIS RELAY IS?? I'm betting at least 50/50 this is still
> my problem.
>
> Ernie, mine has the push-button gear selector.
>
> Bill, your suggestion about checking the barrel connectors was good
> too. I had a problem there too. I'm not sure how these problems
> are related, but probably somehow. I had a melted pin in one of
the
> connectors. It was the 12v supply to the ignition switch. I'm
> suspecting it had been going bad with corrosion, and somehow all
> my "trouble shooting" was the end of it. I corrected that problem.
>
> Thank,
> Alan
>
>
> --- In WanderlodgeForum@yahoogroups.com, "Alan"
> wrote:
> >
> > Well, after many hours this is where I currently am.
> >
> > 1. I have zero volts going to my ZF ECU.
> > 2. The coach won't start. Now I'm pretty sure that's because
> > without voltage to my ECU, the coach doesn't know if it's in gear
> or
> > not. (I can jump my starter solenoid and it starts.)
> > 3. I talked to Dan at ZF in Chicago and he was quite helpful. He
> > told me how to check voltage on the ZF. BUT he didn't know where
> the
> > ZF gets it's power off the coach.
> > 4. I am getting volts out of my 75amp ignition relay with the key
> > turned on.
> >
> > There are bunches of ZF wires behind the grill in the steering
> > column access panel. There are also two silver boxes with what
> are
> > apparently ZF wires going in and out of them. The boxes are
about
> > 4" x 4" x 1". However, I know these aren't the ZF ECU. It is
> > located underneath the push-button gear selectors by the driver.
I
> > don't know if they have anything to do with power.
> >
> > Questions (If anyone knows):
> > 1. Where/how does the ZF get power from the coach?
> > 2. Does the power go through the filtered power source under the
> > couch?
> > 3. What would keep me from getting any power to the ECU?
> >
> > Tomorrow I'm ordering a full set of electronic drawings, but in
> the
> > mean time my neighbors would appreciate it if I can get the coach
> > moved from the street.
> >
> > Thanks,
> > Alan Johnson
> > 972.769.2526
> > 87FC35
> >
>