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[GMCnet] Onan control board [message #162480] Thu, 08 March 2012 16:46 Go to next message
nancy mercier is currently offline  nancy mercier   United States
Messages: 62
Registered: February 2012
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Member
Now that my blower works, I'm going after the generator. Cranks but won't
start. I'm checking the solinoid by checking for 12 v between terminals 1
and 10...question is, there are two number 1 terminals. Which to use?

Also my number 6 is empty, no wires attatched...normal?

Thanks..Nancy
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Re: [GMCnet] Onan control board [message #162482 is a reply to message #162480] Thu, 08 March 2012 17:03 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
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Senior Member
Nancy,

The A/C high blower should only work when the engine is running. If
it's running otherwise, you have another problem. If the other speeds
are not working, you may have a problem with the resistor pack which
is mounted in the left (driver's) side of the HVAC box under the hood.
Be sure its connector has good contacts and that it's securely
plugged in. Don't be surprised if you find one of the contact bent
over (for the yellow wire, IIRC) -- that disables the always-on low
speed blower.

For the Onan, start by downloading this:

http://gmcws.org/Tech/dsimmons/onan/onan.html

Also, if you don't have the Onan manual, it's available at www.bdub.net.

If the troubleshooting guides in those don't enable you to find the
problem, at least they'll enable you to ask more specific questions
here.

Oh yeah, #1=#1 -- they're both the same circuit. And #6 should,
indeed, be vacant.

You may find this circuit diagram easier to read than the original --
I, as a EE, could hardly follow that one, so redrew this. Disregard
the 4kW label -- they're identical.

https://docs.google.com/viewer?url=http%3A%2F%2Fwww.gmcmhphotos.com%2Fphotos%2Fdata%2F5813%2FKH_Onan_Wiring1.pdf

or

http://goo.gl/Wp5x9

Ken H.


On Thu, Mar 8, 2012 at 5:46 PM, nancy mercier wrote:
> Now that my blower works, I'm going after the generator. Cranks but won't
> start.  I'm checking the solinoid by checking for 12 v between terminals 1
> and 10...question is, there are two number 1 terminals.  Which to use?
>
> Also my number 6 is empty, no wires attatched...normal?
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Onan control board [message #162483 is a reply to message #162480] Thu, 08 March 2012 17:04 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member

On Mar 8, 2012, at 3:46 PM, nancy mercier wrote:

> Now that my blower works, I'm going after the generator. Cranks but won't
> start. I'm checking the solinoid by checking for 12 v between terminals 1
> and 10...question is, there are two number 1 terminals. Which to use?
>
> Also my number 6 is empty, no wires attatched...normal?
>
> Thanks..Nancy
Some of the terminals have the same number and they both connect together.
You are correct that terminal 6 is not used.
Be sure to remove the control board cover and check to see that the fuse is not blown.

If you want to check to see if you have a bad control board just put a jumper between terminals 9 and 5. This will give power to the fuel pump and ignition coil.
You should hear the pump running. You then push the start button and if the Onan starts you will know that you have something wrong with the board. One or both relay or bad capacitor or broken circuit board leads.

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: [GMCnet] Onan control board [message #162484 is a reply to message #162482] Thu, 08 March 2012 17:09 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Registered: January 2004
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Ken
Both of the links that you sent require your personal password to sign in.
I have already emailed Nancy a jpg image of your diagram.

Emery Stora

On Mar 8, 2012, at 4:03 PM, Ken Henderson wrote:

> Nancy,
>
> The A/C high blower should only work when the engine is running. If
> it's running otherwise, you have another problem. If the other speeds
> are not working, you may have a problem with the resistor pack which
> is mounted in the left (driver's) side of the HVAC box under the hood.
> Be sure its connector has good contacts and that it's securely
> plugged in. Don't be surprised if you find one of the contact bent
> over (for the yellow wire, IIRC) -- that disables the always-on low
> speed blower.
>
> For the Onan, start by downloading this:
>
> http://gmcws.org/Tech/dsimmons/onan/onan.html
>
> Also, if you don't have the Onan manual, it's available at www.bdub.net.
>
> If the troubleshooting guides in those don't enable you to find the
> problem, at least they'll enable you to ask more specific questions
> here.
>
> Oh yeah, #1=#1 -- they're both the same circuit. And #6 should,
> indeed, be vacant.
>
> You may find this circuit diagram easier to read than the original --
> I, as a EE, could hardly follow that one, so redrew this. Disregard
> the 4kW label -- they're identical.
>
> https://docs.google.com/viewer?url=http%3A%2F%2Fwww.gmcmhphotos.com%2Fphotos%2Fdata%2F5813%2FKH_Onan_Wiring1.pdf
>
> or
>
> http://goo.gl/Wp5x9
>
> Ken H.
>
>
> On Thu, Mar 8, 2012 at 5:46 PM, nancy mercier wrote:
>> Now that my blower works, I'm going after the generator. Cranks but won't
>> start. I'm checking the solinoid by checking for 12 v between terminals 1
>> and 10...question is, there are two number 1 terminals. Which to use?
>>
>> Also my number 6 is empty, no wires attatched...normal?
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: [GMCnet] Onan control board [message #162487 is a reply to message #162484] Thu, 08 March 2012 17:32 Go to previous messageGo to next message
Steve Clevenger is currently offline  Steve Clevenger   United States
Messages: 7
Registered: January 2004
Karma: 0
Junior Member
Hmm..popped right up for me.

At 05:09 PM 3/8/2012, you wrote:
>Ken
>Both of the links that you sent require your personal password to sign in.
>I have already emailed Nancy a jpg image of your diagram.
>
>Emery Stora

Steve Clevenger
1976 Transmode 230
West Fork, AR

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Re: [GMCnet] Onan control board [message #162488 is a reply to message #162484] Thu, 08 March 2012 17:40 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Oh my! Methinks that's another symptom of the problems Billy & I have
been having -- the photo site software has us confused. :-)

Ken H.


On Thu, Mar 8, 2012 at 6:09 PM, Emery Stora wrote:
> Ken
> Both of the links that you sent require your personal password to sign in.
> I have already emailed Nancy a jpg image of your diagram.
>
> Emery Stora
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Onan control board [message #162490 is a reply to message #162480] Thu, 08 March 2012 17:50 Go to previous messageGo to next message
MikeT   United States
Messages: 225
Registered: November 2009
Location: Marine City, Michigan
Karma: 0
Senior Member
My Onan would crank and crank but not start. I called Jim Bounds and he had me put a jumper from the positive cable on the starter direct to the coil. Fired right up. Disconnected the jumper and continued to run. Starts without the jumper now. Said something like low voltage going to the K-relay. Give it a try it worked for me.

Mike Thomas Marine City, MI 77 ex Palm Beach
Re: [GMCnet] Onan control board [message #162491 is a reply to message #162480] Thu, 08 March 2012 17:51 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
nancy mercier wrote on Thu, 08 March 2012 15:46

Now that my blower works, I'm going after the generator. Cranks but won't
start. I'm checking the solinoid by checking for 12 v between terminals 1
and 10...question is, there are two number 1 terminals. Which to use?

Also my number 6 is empty, no wires attatched...normal?

Thanks..Nancy
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As others mentioned, the best thing to do is jumper the terminals but also check to see if the choke rod is moving when you activate the starter. There is a rod that goes from the choke lever at the top of the carburetor that goes to a coil looking device on the exhaust manifold. You may want to move the rod back and forth while cranking to see if that helps.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] Onan control board [message #162498 is a reply to message #162488] Thu, 08 March 2012 20:34 Go to previous message
Billy Massey is currently offline  Billy Massey   United States
Messages: 916
Registered: January 2004
Location: Central Texas
Karma: 1
Senior Member

Google simply wants everyone that looks at the doc to be a member of google.
It is asking for each viewers google credentials. Those who are already
logged into google will gain immediate access.

bdub


-----Original Message-----
From: On Behalf Of Ken Henderson

Oh my! Methinks that's another symptom of the problems Billy & I have been
having -- the photo site software has us confused. :-)

Ken H.


On Thu, Mar 8, 2012 at 6:09 PM, Emery Stora wrote:

> Both of the links that you sent require your personal password to sign in.
> I have already emailed Nancy a jpg image of your diagram.
>
> Emery Stora


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bdub
bdub.net
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