boler76
Generac 7KW LV432;;Model 58370;; ser# 8760983;;
  Controller 0J0064  NG supply is 1"
the choke  has no power source from the control board, a new board was sent from Generac and it  also does not have any connection from the  choke terminal to the internal workings of the  controller,  Is there a  Rev to this board that has the pulsing  supply needed for the choke.
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MacL
it uses wire 56 as a power supply.  56 starts from the six wire connector cavity 11.  It is hot when cranking.  There is a splice on this wire as it also powers the starter contactor.  A problem at that splice could cause no power to the choke, but if the starter is engaging and cranking, the wire 56 output from the board is good.  You can carefully probe the choke connector wire 56 (do not insert any object into the terminal, just touch it) and see if it has 12 volts during cranking with the gas off to prevent actual starting and keep the reading available longer.

The choke's patterned movements are controlled on the ground side by the board with wire 90, same six wire connector cavity 15.


56 won't be hot while the engine is running, so apparently no juice to the choke = choke open.  Energized = closed.  So to close the choke during cranking wire 90 is grounded by the board via terminal 15 in the six wire connector.

The six wire connector (wires 14, 23, 15b, 0, 56, 90), plugs into an 18 cavity socket on the controller.  That socket should have a male pin in both cavity 11 and 15.
State your problem, not your diagnosis.
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Peddler
I'm not positive about this because I haven't looked in a tech manual to check but I think on those units the choke stays energized the entire time the unit cranks and does not drop out until it starts.
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boler76
Thanks for the prompt reply, yes I have wiring diagram and trouble shooting manual for this machine but the problem is in the control board, there is no connection between the board and the terminal that the wire is connected to that feeds the choke, the terminal is there and labelled correctly but no internal connection from the printed circuit board, I contacted Generac cust service previously about this problem and they provided a duplicate board, and it is wired the same, When this unit was under warranty I had the service rep for this area come 3 times and they could not fix it, I think there should be a Rev for this board that I don't have ??? Thanks again
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Peddler
The wire to the board provides the ground not the positive.
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boler76
I am sorry I cant explain this properly, but wire connected to terminal 15 is dead ended there, No connection ever to ground during cranking, I have taken the control board out of the enclosure and had a good visual of it and there is no internal connection to 15 in the controller?? ???
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cookelec
The choke should energize while cranking as MacL said. Wire 56 energizes the starter contactor and the choke but it appears you have no ground. Place a temporary jumper from wire 90 to battery negative (0) and see if the choke works correctly.  
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cookelec
Don't leave the jumper on for extended time because I think that choke coil is only rated at 6VDC. I will check and find out.
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boler76
The choke energizes when it has a ground temporarily applied when cranking only... there is no internal connection to terminal 15 from the printed circuit board. I do not have a wiring diagram of the printed circuit board to see where the pulsed ground (-) is supposed to originate, Thanks for all the help
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MacL
I've often wondered about that choke coil saying "6 volts" on it, and how that is achieved.  Are we guessing there must be a resistance on the board that the ground wire 90 that it is fed through before it gets to ground? 
State your problem, not your diagnosis.
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boler76
I am thinking the reason for a 6v choke is to make sure it snaps closed and since it is only supposed to be energized intermittently while engine cranks , it should be OK on 12v, but mine doesnt work at all, I think there should be a revised circuit board but why,, and I have a new board that gives same results, Choke works when I ground the 15 terminal momentarily while it is cranking???
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murphy
I have no idea but varying resistances could probably be used to get multiple choke positions.

That could be a multi-layer board.  You would not be able to see an internal trace unless the board was transparent.
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Cobranut
If there is supposed to be a voltage dropping resister in the ground circuit, an open resistor would cause the problem you describe.
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boler76
So getting back to my original question, is there a rev to the circuit board 0J0064 that would include the choke pulse, The circuit board that I have and have 2 of, has no connection in the board to pin 15 on the board end, I have just again taken the board out and very closely examined it, there are connections to the other pins but none to 15, Has anyone else had this problem and if so what was the remedy? Thanks
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Peddler
There is no revision for the controller 0J0064.  Have you ohmed the 90 wire to the controller from the choke solenoid?  Have you ohmed the #56 wire from the choke solenoid to the #56 wire on the start solenoid?  Have you verified the ground from the board to the negative battery terminal to be less than 1 ohm?  You have some other problem other than a bad board in my opinion.  Have you verified the #90 wire is landed in the correct pin position and that the pin is got a good connection to the wire?
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JayH
MacL wrote:
I've often wondered about that choke coil saying "6 volts" on it, and how that is achieved.  Are we guessing there must be a resistance on the board that the ground wire 90 that it is fed through before it gets to ground? 


It's only energized during cranking when there's a heavy load on the battery. Also, it's an intermittent application where the solenoid is only powered for a few seconds until the engine starts. Applying 12 volts to it continuously would likely cause overheating and damage but in this application it's not a problem. The 6-volt rating ensures that it has plenty of power to operate reliably during the brief cranking interval.
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JayH
boler76 wrote:
So getting back to my original question, is there a rev to the circuit board 0J0064 that would include the choke pulse, The circuit board that I have and have 2 of, has no connection in the board to pin 15 on the board end, I have just again taken the board out and very closely examined it, there are connections to the other pins but none to 15, Has anyone else had this problem and if so what was the remedy? Thanks


Are you sure it isn't a multi-layer board with an internal trace? The circuit boards are all made from the same Gerber file and there are thousands of generators out there with functional choke solenoids. Perhaps the wire is landed in the wrong cavity of the Molex connector? If you connect an ohmmeter between that pin and ground, do you see a low resistance during cranking? Perhaps the wire is open at the connector pin.
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boler76
Well to continue my testing , today I shut off fuel supply, connected my Fluke multimeter to pin J2-11, ran starter and got the 12v dc reading to ground, then with same meter connected to ground and on Ohm scale probed on to pin J2-15, ran starter and absolutely open circuit all the time, when visually examining the board the pin J2-15 has no connection to it, all the other connections are plainly visible on the board, does anyone have a schematic of the board? 0J0064 rev A K1401 Thank you
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Peddler
Are you sure the #90 wire is in the J2 #15 location, there are several empty locations on that connector and the wire could be wrong from the factory.  That makes more sense than two bad controllers. 
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boler76
I tested from the board side of the J2-15 not from the # 90 wire
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MacL
Sometimes the choke connector doesn't make good contact and needs to be bypassed.  

Especially with the history on this machine it is likely that someone stuck a paper clip in the female choke connector and spread some terminals.  That connector cannot have anything inserted into it.  And you know someone stuck something in it.  

Typically you'd bypass the connector by cutting both parts off and butt splicing the wires together permanently.

I think bypassing the connector would be worth a shot, because it is a known failure point, and it would remove that variable from the equation.  Try to have an open mind.  Sounds like your certainty that the boards were all messed up in manufacturing is preventing you from doing a proper diagnosis.
State your problem, not your diagnosis.
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