I have an older Z master G3 model 74937 which has been great. Except that it dies when it gets around 20F (or -5 Celsius) ambient temp when going into neutral, and won't crank afterwards.
Before anyone asks what I can possibly mow in the winder (as I am sure you are wondering!), my wife uses the mower to pull her small manure spreader.
This happened 3 month ago and 2 weeks ago. The mower is running, parking brake and PTO off, driver seated, and when putting the arms out (to go in neutral) the engine shut off immediately, as if a safety interlock is triggering. Afterwards, when trying to start, there is no crank, no click whatsoever, no solenoid noise. Three months ago, the issue seemed to go away after the weather warmed back up, and my wife cleaned the safety switches. This time, its been cold for 2 weeks and still no luck, mower is stuck. This time also, it was running in cold weather, PTO and parking brake off, driver seated, and it died when going in neutral. No crank no click afterwards.
I checked the fuses, new battery, then used the service manual procedure to check seat sensor, both arms sensors, parking brake sensor, PTO switch, ignition contact switch, ignition relay. All those components tested OK. The TVF diode was bad, I replaced it, no improvement. I bypassed each safety sensor and PTO switch with a wire, no luck. The starter solenoid is not getting 12V on the signal wire when starting. If I apply 12V to the solenoid signal wire, the engine will start cranking.
I thought the hour meter could have been damaged from the lack of protection from the TVF diode being dead. The hour meter most of the time did not show the gas level or the interlock arrows (showing which safety is on or off) even when the mower was running.
I put a new hour meter on, which showed the interlock safety were all correctly ON and ready to start, went to start, and got nothing. Nothing, except that the new hour meter would not show the interlock safety arrows anymore.
The hour meter modules (both new and old) display has been inconsistent. Occasionally when reconnecting it, it will show the interlock safety arrows. Then that goes away when trying to start. I tried warming the module in the house in case there would be a temperature sensor embedded in it, no luck.
Any idea of something to check that I did not check yet? I have not been able to check much of the wiring so far, it is bitter cold outside and there is a bunch of snow.
Would anyone know where I could find some documentation on the hour meter module harness (part #117-3882) wiring diagram and signals? I want to use this to diagnose my wiring: is there a wiring issue in the safety switches, in the wires to the solenoid, to the ignition switch, is it getting 12V etc...
Any documentation on how to bypass the hour meter module/safety interlock module is also much welcome.
Below is what the new hour meter module/safety interlock looks like in each key position, after it stopped showing the safety interlocks on the first start try. Old hour meter shows the same except 1500hrs.
The bolts are off because I have been bypassing or diagnosing a bunch of stuff.
Before anyone asks what I can possibly mow in the winder (as I am sure you are wondering!), my wife uses the mower to pull her small manure spreader.
This happened 3 month ago and 2 weeks ago. The mower is running, parking brake and PTO off, driver seated, and when putting the arms out (to go in neutral) the engine shut off immediately, as if a safety interlock is triggering. Afterwards, when trying to start, there is no crank, no click whatsoever, no solenoid noise. Three months ago, the issue seemed to go away after the weather warmed back up, and my wife cleaned the safety switches. This time, its been cold for 2 weeks and still no luck, mower is stuck. This time also, it was running in cold weather, PTO and parking brake off, driver seated, and it died when going in neutral. No crank no click afterwards.
I checked the fuses, new battery, then used the service manual procedure to check seat sensor, both arms sensors, parking brake sensor, PTO switch, ignition contact switch, ignition relay. All those components tested OK. The TVF diode was bad, I replaced it, no improvement. I bypassed each safety sensor and PTO switch with a wire, no luck. The starter solenoid is not getting 12V on the signal wire when starting. If I apply 12V to the solenoid signal wire, the engine will start cranking.
I thought the hour meter could have been damaged from the lack of protection from the TVF diode being dead. The hour meter most of the time did not show the gas level or the interlock arrows (showing which safety is on or off) even when the mower was running.
I put a new hour meter on, which showed the interlock safety were all correctly ON and ready to start, went to start, and got nothing. Nothing, except that the new hour meter would not show the interlock safety arrows anymore.
The hour meter modules (both new and old) display has been inconsistent. Occasionally when reconnecting it, it will show the interlock safety arrows. Then that goes away when trying to start. I tried warming the module in the house in case there would be a temperature sensor embedded in it, no luck.
Any idea of something to check that I did not check yet? I have not been able to check much of the wiring so far, it is bitter cold outside and there is a bunch of snow.
Would anyone know where I could find some documentation on the hour meter module harness (part #117-3882) wiring diagram and signals? I want to use this to diagnose my wiring: is there a wiring issue in the safety switches, in the wires to the solenoid, to the ignition switch, is it getting 12V etc...
Any documentation on how to bypass the hour meter module/safety interlock module is also much welcome.
Below is what the new hour meter module/safety interlock looks like in each key position, after it stopped showing the safety interlocks on the first start try. Old hour meter shows the same except 1500hrs.
The bolts are off because I have been bypassing or diagnosing a bunch of stuff.
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