Grady22
Hello to all- Just installed a new Generac 16KW air cooled unit. New battery. When switch is put in manual, I hear some faint clicking from the SCR and at the starter. Using the manual troubleshooting guide, I had battery checked and it was OK. Performed checks on SCR and found that it was getting voltage but only for a second at the most. I disconnected the SCR completely and applied 12 VDC to the coil and had continuity through its contact, SCR good. Since the voltage that operates the SCR comes from the PCB, I think the PCB is bad. Any thoughts? Has anyone had the same issue?

Regards
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zen
Hi Grady22.This seems being the same issue i will have to go troubleshoot tomorrow.And here it forecast an icestorm for holliday.I wonder if there is a way to bypass the PCB to start the gen and use it in case a power failure occur while waiting for new part.
Ty and play safe.
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78buckshot
Grady22, I would check for poor connectors at the controller, look for pins and sockets being deformed or not seated in the plastic connector. If all looks good there then you could disconnect the wires on the coil side of the SCR and apply 12 volts to see if the unit will crank ok. While you have the wires off of the SCR you can check for 12 volts when the manual button is depressed.
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78buckshot
Zen, your machine does not have the same SCR that the bigger units have, only the starter contactor or starter solenoid that I mentioned in your first post.
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78buckshot
Zen, I'm sorry, I confused two posts. The answer I gave in the above post is comparing a single cylinder generator to a twin cylinder, the singles don't have a starter contactor relay (SCR).
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zen
the one they called me for is a 16 kw also model 5244
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MacL
zen wrote:
Hi Grady22.This seems being the same issue i will have to go troubleshoot tomorrow.And here it forecast an icestorm for holliday.I wonder if there is a way to bypass the PCB to start the gen and use it in case a power failure occur while waiting for new part.
Ty and play safe.

I've used an ice cube relay in place of an scr while waiting on an scr to come in.  If you use some other style of 12 v normally open relay, be sure your connections stay in place and don't short.  The scr is rated for more current than the panel relay.  But the panel relay is rated for 10 amps.
State your problem, not your diagnosis.
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grsthegreat
I had a similar thing happen to a 22 KW i installed, but the control panel screen would also reset. That one turned out to be the ground wire wasn't seated on the engine mount......was hand tight from the factory. When i went to start it, i heard a faint clicking only.
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78buckshot
 Poor or no grounds will cause some strange symptoms and will have you second-guessing your diagnostic skills.
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Grady22
Problem solved, the black ground cable from the battery to the engine base was loose. Tightened bolt up and unit started normally. Quality control at Generac is lacking.
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