John Deere 997 Seat Safety Not Working

[Auto Doc's]

Go to the link Kenbu sent you and scroll down the page, "old cajun" has it all laid out

 

[jshep1102]

Go to the link Kenbu sent you and scroll down the page, "old cajun" has it all laid out

The screenshots of ways to check the timer module are for a type different than mine. It shows a square 4 pin plug in a 2x2 configuration. Mine is a 1x4 flat configuration. I attached pics of the 2 different styles I've found.
I was wishing Kenbu's pic showed wire colors so I could check to see if mine had the same colors.

 

[StarTech]

Here is a hint from the 777, 797 that uses the same delay module.

1. A delay module might be installed in place of wire 477 yellow. The
delay module prevents errant engine shut-off caused by the seat switch
being momentarily disengaged due to operating on very rough terrain.

if this is correct and the Z997 is using the wiring numbers then you can remove the delay module and install a test jumper to see if the module is the problem area. Just make sure you jump the right two wires. There will be 12v on one of the wires which what activates the module which in turn activates the magneto stop and keeps the fuel solenoid active during about a 2 sec delay. This circuit controls the magneto stop relay and the fuel solenoid on the 777, 797 mower.

But as I said I don't have the SM for the International version of the Z997 at hand. So this is just a guess.

 

[jshep1102]

Here is a hint from the 777, 797 that uses the same delay module.

1. A delay module might be installed in place of wire 477 yellow. The
delay module prevents errant engine shut-off caused by the seat switch
being momentarily disengaged due to operating on very rough terrain.
View attachment 72133
if this is correct and the Z997 is using the wiring numbers then you can remove the delay module and install a test jumper to see if the module is the problem area. Just make sure you jump the right two wires. There will be 12v on one of the wires which what activates the module which in turn activates the magneto stop and keeps the fuel solenoid active during about a 2 sec delay. This circuit controls the magneto stop relay and the fuel solenoid on the 777, 797 mower.

But as I said I don't have the SM for the International version of the Z997 at hand. So this is just a guess.

If it is a failed delay module, it has failed in the "energized" condition and is keeping the fuel solenoid and/or magneto stop from killing the engine when the operator leaves the seat for >2sec. It's a rainy day today so I'll have to do some more testing tomorrow afternoon when the rain is supposed to stop. Thanks for the help Star!

 

[masterchief davis]

Hi guys,
I'm working on a John Deere 997 Z-Trak for a friend and I'm trying to get the seat safety switch to work. I think it may be an early 2000's model (ID# DM997SC020068).

Complaint - mower will not cut off while mower deck is engaged and you lift your butt out of the seat.

Things I've done/found:
1. Seat safety switch confirmed to close when switch depressed and open when nobody in the seat.
2. Mower start and runs/mows normally otherwise.
3. neutral safeties both confirmed to work: i.e. mower won't start with either lever out of neutral position (don't think it has anything to do with the problem but I checked it anyways).
4. Brake safety works as expected (again, don't think it has anything to do with the problem but I checked it anyways)
5. Previous owner had a jumper piggybacked from red wire of seat timer delay module running to the red wire on shutoff solenoid valve. No idea why it was installed so I disconnected it and everything is still acting the same.
6. Seat timer delay module has zero VDC on red wire with key off and 12+VDC with key in run position. (4 pin plug associated with this module)
7. I swapped the Start relay (7th of 10 relays) with the Seat relay (9th of 10 relays) to see if it was a bad seat relay. No change. Mower still starts and seat switch still not working.

Could it just be a bad seat delay module? Thanks in advance for any help you can provide.
Jerry

its probably the buttons under the seat not adjusted for making contact with seat raised try pushing the buttons with seat raised,

 

[StarTech]

its probably the buttons under the seat not adjusted for making contact with seat raised try pushing the buttons with seat raised,

This system uses 12 vdc thru the seat switch and the time delay to activate a relay and the fuel solenoid so the engine will start and run. It must become an open circuit to disengage the relay and to deactivate the fuel solenoid. This means the seat switch is NO and not a NC switch.

 

[jshep1102]

This system uses 12 vdc thru the seat switch and the time delay to activate a relay and the fuel solenoid so the engine will start and run. It must become an open circuit to disengage the relay and to deactivate the fuel solenoid. This means the seat switch is NO and not a NC switch.

Correct, switch is open with nobody in the seat. It closes with relatively light pressure on the seat so i'm confident this switch is not the issue.
I stopped at 2 local shops today trying to find an electrical schematic to aid in troubleshooting but neither could access it. The closest john deere dealer is over an hour away.