[chadjones999]

I bet I could bypass any unit. I've void warranty LOL . most likely 1 of 2 ways the sensor works, 1) like a switch when set to alarm it opens or closes a circuit. easy to bypass. , 2) harder but not by much it has a resistance value , like X-ohms when alarming or X-ohms when not. just need to find this value and use a restitor to simulate .

 

[Colt Carson]

Kinda comical some of the things owner's manuals tell you not to do nowadays. But I’ve noticed people don’t seem to read owner's manuals, so there’s that…

 

[chadjones999]

hey im looking for a remote start kit for my predator 9500. anyone know where I can find this ?

 

[bassguitarist1985]

I bet I could bypass any unit. I've void warranty LOL . most likely 1 of 2 ways the sensor works, 1) like a switch when set to alarm it opens or closes a circuit. easy to bypass. , 2) harder but not by much it has a resistance value , like X-ohms when alarming or X-ohms when not. just need to find this value and use a restitor to simulate .

The 2nd method you describe is not how a CO sensor works. Unfortunately is far more complicated than a resistance plot. It works on a difference of voltage in the control circuit that runs it. Subbing in a simple resistor wont bypass it. The control circuit can operate as a simple on/off switch based on the sensors output such as killing the ignition spark on the kill wire terminal. That control circuit may be far more complex such as outputting a pulse signal to the inverter module, to which that module translates as an on/off state for the inverter output and kills the ignition. Without that pulse signal, the inverter will shut down the generator after a few seconds. Sadly these sensors are far from simple in many cases.

Take this sensor for example: https://www.digikey.com/en/products/detail/spec-sensors-llc/110-102/6136363

All CO sensors have a shelf and service life. That is all determined by RH and temperature. It also responds differently too based on those specs. So how you store your generator, if the RH/Temp is frequently high, it shortens the life expectancy.

Typically they are rated for 10 years of service life, but at ideal environmental conditions. More realistically in practice, these sensors will see about 5-7years before failing. My technician contact at Firman told me that the control circuit design they had on their sensors were too oversensitive, so a "bad" batch made the sensors problematic. They have since corrected it, and if you do have a faulty sensor, it is easily replaced without digging into the wiring/voiding warranty.

The circuit design in general is intriguing to me, but I can see how complexity causes diagnostic difficulty. As someone else posted, Sensors cannot fix stupid!

 

[chadjones999]

The 2nd method you describe is not how a CO sensor works. Unfortunately is far more complicated than a resistance plot. It works on a difference of voltage in the control circuit that runs it. Subbing in a simple resistor wont bypass it. The control circuit can operate as a simple on/off switch based on the sensors output such as killing the ignition spark on the kill wire terminal. That control circuit may be far more complex such as outputting a pulse signal to the inverter module, to which that module translates as an on/off state for the inverter output and kills the ignition. Without that pulse signal, the inverter will shut down the generator after a few seconds. Sadly these sensors are far from simple in many cases.

Take this sensor for example: https://www.digikey.com/en/products/detail/spec-sensors-llc/110-102/6136363

All CO sensors have a shelf and service life. That is all determined by RH and temperature. It also responds differently too based on those specs. So how you store your generator, if the RH/Temp is frequently high, it shortens the life expectancy.

Typically they are rated for 10 years of service life, but at ideal environmental conditions. More realistically in practice, these sensors will see about 5-7years before failing. My technician contact at Firman told me that the control circuit design they had on their sensors were too oversensitive, so a "bad" batch made the sensors problematic. They have since corrected it, and if you do have a faulty sensor, it is easily replaced without digging into the wiring/voiding warranty.

The circuit design in general is intriguing to me, but I can see how complexity causes diagnostic difficulty. As someone else posted, Sensors cannot fix stupid!

I still think I could bypass it, I really don't think that the Chinese generators are going to spend much money on anything so complex .( maybe honda EFI model ) Not that its impossible to do so. Just all about $$ . Also my warranty is only 90 days on the predator 9500 from the store unless you but a 2 year warranty for 500 plus $ ... and they don't offer anything higher so the 5 to 7 years you are saying is likely . you will be way out of warranty . and truth be told the generator itself will be out of life at this point. from my experiacne you start have many other issues before then , I.E. replacing the carb , etc leaking or burning oil badly

 

[OrlyP]

There are YT videos on how to bypass the CO sensor on the Predator 9500... The guy below just unhooked a hardness going to the sensor module. But in addition to that, he also cut a 2nd set of wires but then bridged the two wires together on the engine side to fool it to keep running.

So it appears that in this setup, the CO sensor is configured for normally-closed (NC) and will switch open when it detects CO to kill the engine.

This is crucial info if you're in a bind due to a faulty sensor preventing the engine from starting. It's really up to you if you want to disable it now or after it has failed.

 

[chadjones999]

There are YT videos on how to bypass the CO sensor on the Predator 9500... The guy below just unhooked a hardness going to the sensor module. But in addition to that, he also cut a 2nd set of wires but then bridged the two wires together on the engine side to fool it to keep running.

So it appears that in this setup, the CO sensor is configured for normally-closed (NC) and will switch open when it detects CO to kill the engine.

This is crucial info if you're in a bind due to a faulty sensor preventing the engine from starting. It's really up to you if you want to disable it now or after it has failed.

so like I said in my post ... its typically like a switch that is either normally open or closed. and could be bypassed. and yes it could be done more complexly but is not normally the case because that cost money and they always want the cheap way out.

 

[chadjones999]

The 2nd method you describe is not how a CO sensor works. Unfortunately is far more complicated than a resistance plot. It works on a difference of voltage in the control circuit that runs it. Subbing in a simple resistor wont bypass it. The control circuit can operate as a simple on/off switch based on the sensors output such as killing the ignition spark on the kill wire terminal. That control circuit may be far more complex such as outputting a pulse signal to the inverter module, to which that module translates as an on/off state for the inverter output and kills the ignition. Without that pulse signal, the inverter will shut down the generator after a few seconds. Sadly these sensors are far from simple in many cases.

Take this sensor for example: https://www.digikey.com/en/products/detail/spec-sensors-llc/110-102/6136363

All CO sensors have a shelf and service life. That is all determined by RH and temperature. It also responds differently too based on those specs. So how you store your generator, if the RH/Temp is frequently high, it shortens the life expectancy.

Typically they are rated for 10 years of service life, but at ideal environmental conditions. More realistically in practice, these sensors will see about 5-7years before failing. My technician contact at Firman told me that the control circuit design they had on their sensors were too oversensitive, so a "bad" batch made the sensors problematic. They have since corrected it, and if you do have a faulty sensor, it is easily replaced without digging into the wiring/voiding warranty.

The circuit design in general is intriguing to me, but I can see how complexity causes diagnostic difficulty. As someone else posted, Sensors cannot fix stupid!

it appears NOT , see
OrlyP post below . its a simple bypass switch...........like I said first LOL

 

[bassguitarist1985]

it appears NOT , see
OrlyP post below . its a simple bypass switch...........like I said first LOL

Well then........thankfully it is a simpler circuit for this model! 🙂

 

[OrlyP]

To be fair, I agree with bassguitarist that it is design-specific. HF or their OEMs could anytime change their CO sensor design to account for parts availability. There are no standards afaik on how a sensor should shutdown the engine. It just needs to happen.

 

[chadjones999]

To be fair, I agree with bassguitarist that it is design-specific. HF or their OEMs could anytime change their CO sensor design to account for parts availability. There are no standards afaik on how a sensor should shutdown the engine. It just needs to happen.

true

 

[Colt Carson]

I’m against these CO sensors, but somebody is crazy to make a video demonstrating how to defeat a "safety device". Unless you have no assets to be gained in a lawsuit.

 

[chadjones999]

I’m against these CO sensors, but somebody is crazy to make a video demonstrating how to defeat a "safety device". Unless you have no assets to be gained in a lawsuit.

yes asking for trouble (nowadays) , I better download it before its gone!

 

[OrlyP]

The video is a year old with 11k views. I doubt it's going anywhere.

 

[chadjones999]

The video is a year old with 11k views. I doubt it's going anywhere.

that was more of a joke

 

[OrlyP]

that was more of a joke

lol

In my defense, sarcasm doesn't always get across clearly over written mediums. But I'd be sure to take my sarcasm pills from now on.

Anyway, that's the gist of it. For better or for worse, remove/disable the built-in CO detector at your own risk.

When the time comes and you're planning on selling or loaning the generator to someone else, you should either put it back together OR expressly inform the other party whether or not the CO detector is working or not.

 

[NAveton]

Just know that bypassing safety systems is not the best way to go about it. That said, I can understand your motivation to do so. Just be aware of the consequences when carrying out such drastic methods.

If the generator is solely going to be operated in an open area (as it should be) and away from living spaces, you could probably be fine with the CO alert disabled. From what I've read, simply disconnecting the wire connector behind the CO module essentially bypasses it.

As to the oil level alert system, there are two or maybe three parts that can go wrong. Most common failure point is the oil level sensor inside the crankcase. 2nd failure point would be the oil sensor module. This is a part that ressembles a small automotive relay, except that it is often encased in metal. It's often found bolted on the engine near where the yellow wire from the sensor goes to. If in doubt, just follow the yellow wire. If the oil alert circuitry is built into the inverter module, that gets us to the possible third cause of failure. The inverter module may be faulty. Without looking at the schematic, I'm willing to bet that your generator has a dedicated oil sensor module (ie. not integrated with the inverter module).

Hello EJ3 and OrlyP. Your posts inspired me to check a few items on my 9500. Bought mine about 2.5 years ago, never put oil or gas in it / never tried starting it until this past weekend. Oil and gas filled up as instructed. Would not start. Gas seemingly flowing through, nice bluewhite spark. I started tinkering with the wires on the oil fill side. I narrowed it down to the little silver square device showing in your pics. When I detach it from the screw holding it to the generator housing, mine starts and runs great. From the owner's manual parts list and diagram, I think it is item 52 which is labeled 'oil alert' or 'module'. Do you or anyone else believe just this device not being grounded essentially disabling it / bypasses it allows the engine to run? That this silver box / oil alert item is defective? Could anyone confirm this is the low oil sensor (LOS)? If it is the LOS, is it critical I replace it? It is not very hard to check the oil level using the dipstick. Thanks!

 

[GenKnot]

the little silver square device

Similar to this?

If so, that contains an SCR that is triggered by the oil level sensor inside the crankcase. The yellow wire would go to the oil level sensor.

The oil level sensor in the crankcase is basically a float device. When the oil gets too low, the sensor triggers the SCR to turn on and then the gen is shut off.

If the float is in the low oil level position, the yellow wire to the float will show a ground (continuity to case). With proper oil level in the gen, the float should show an open condition.

It could be that since your gen sat for along time with no oil in it, the float is somewhat stuck in the low oil position. Try rocking the gen back and forth (not running) to see if you can get it freed up.

 

[NAveton]

Similar to this?
View attachment 18052

If so, that contains an SCR that is triggered by the oil level sensor inside the crankcase. The yellow wire would go to the oil level sensor.

The oil level sensor in the crankcase is basically a float device. When the oil gets too low, the sensor triggers the SCR to turn on and then the gen is shut off.

If the float is in the low oil level position, the yellow wire to the float will show a ground (continuity to case). With proper oil level in the gen, the float should show an open condition.

It could be that since your gen sat for along time with no oil in it, the float is somewhat stuck in the low oil position. Try rocking the gen back and forth (not running) to see if you can get it freed up.

Thanks for the extra detail explanation. I didn’t think about the ‘float’ device so maybe you’re right that it is stuck from sitting. What does SCR stand for? The pic you shared has two wires, whereas mine has four wires plus it must be using the metal housing it’s bolted to as a ground since when I remove it from the housing, something changes and the engine runs well.

 

[GenKnot]

Yes, some of them have four wires and the metal casing is often used for ground.

SCR is silicon controlled rectifier.