Repairs Electrical Issue I believe

flmeade

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Exmark Laser XS Diesel 60"
Yesterday when I got off the mower I set the parking breaking, throttled down, turned off the PTO and set the steering bars in their usual at rest position.
When I got off the engine died and I could not get it to restart because the starter would not engage.

Bypassed the seat switch and the steering bar safetys but still no luck, no juice to the starter solenoid.

Put a jumper from the solenoid to the battery with the key on and parking brake on and it would crank and start but die immediately.

Tried the same jumper with the parking brake off and it starts and stays running and you can mow all you want. Engage parking break and it dies.

Anybody ever had this problem? I have looked at the electrical diagrams for the diesel and the gas models and the safetys and ignition wiring seem identical.
Short in wiring harness? Brakes safety switch? PTO switch? Ignition switch?

I can't figure out how to bypass the brake safety switch or how to test it. If someone knows please let me know.
As usual I hate to just start throwing parts at it.

Thanks in advance for any feedback or interest in my issue.
 

flmeade

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Off course I checked all fuses, cleaned grounds and swapped out modules since they were all the same.
 

bertsmobile1

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sounds very mch like a faulty brake switch.
They are all very simple plunger switches which open or close the contact between the terminals .
If it has 4 terminals then one pair will be open & close them the plunger is depressed and the other pair will do the opposite.

The switches are quite cheap & suffer from corrosion , arcing & general wear.
Most switches are held in with barbs so the entire switch housing wears and the plunger wears on the contact end.
Flip the seat & locate the switches .
There will be one two or three on each lap bar and one on the parking brake.
Most parking brakes are double switches .
One pair of terminals prevent the engine from cranking unless the brake is on.
The other pair kill the engine if the brake is on and the lap bars move in to the drive position.
When yo pull the plug off the pairs are the terminals that are flat to flat , not edge to edge.
So you can just do an Ohm reading across each pair, plunger in & plunger out
 

flmeade

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That wasn't the problem put a new brake safety switch on the mower with no change. I have a new ignition switch coming Monday if that doesn't fix it I am going to go to installing a momentary switch to manually activate the starter.
 

bertsmobile1

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I don't have any information about your mower & as I am very unlikely to ever see one, not likely to chase it down either.
OTOH you do have one so get your hands on a wiring diagram.
With the bigger mowers a lot of the safetys run via a relay.
I have a bag of short jumpers with a spade on each end to bypass switches & relays.
This is how I diagnose most of these non start situations.
Bypass everything then one by one reconnect a switch or relay till it doesn't start .
ZTR's are easy to trouble shoot cause all of the wiring is there in front of your face.
Pull the plug off the key switch and jump the B & S wires only.
Thus when you are working, the engine can crank, but not start.
If you are a little less brave the hook up a test lamp ( any old globe will do ) between the solenoid wire & a good ground.
Also if you have a 3 wire solenoid try jumping from a good ground to the body of the solenoid as they are body grounded and ZTR's in particular suffer corrosion between the solenoid & the mower thus no ground.
If it has a 4 wire solenoid the other wire is ground and it can also be switched .
Same story for a relay. common wiring to have a starting relay with the ground being switched by a loop through the lap bar switches.
Switching ground contacts seems to confuse a lot of people .
 

flmeade

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Tried a new ignition switch today with no success. I have a one wire solenoid which is getting no power. I can start the mower by putting power to the one wire and that will turn the starter.

But it'll only start if the brake lever is off when I put power to the solenoid and I have already replaced that safety switch. I tried bypassing all the safetys I could, bypassed motion control arms and seat switch.

I have a wiring diagram but it's not helping. Only safety I can't figure out how to bypass is the seat delay safety. That is supposed to let you bounce up off the seat in rough terrain and not kill the engine.
 

bertsmobile1

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Print out the wiring diagram then trace over the wires from the solenoid to the Key switch.
The usual run is S >PTO>parking brake > solenoid
ZTRs then to add lap bars so they go S > PTO > Parking Brake > Lap Bars ( both ) > Solenoid
The seat switch is generally not in the cranking circuit.
The seat switch is generally a kill wire so it will allow the engine to crank but not run.

There is a second safety circuit that goes:- lap bars > parking brake > magneto
This is designed to prevent you driving with the brake on.
 

flmeade

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Re: Electrical Issue I believe no crank

I talked to a Exmark tech guy and he sent me a flow chart to properly check all electrical and safety switches in the proper order. Big help. Ended up being the PTO switch was faulty and worked sometimes and sometimes not. It would start the blades but no send a signal to the safety circuit.
I fixed it by giving it a good wack on the top with the handle of a large screw driver.

I am trying to upload the flow chart for other Exmark users hope it works if not send me an email address and I'll send it that way.
 

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old man 67

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I have an Exmark LZX801KA606, the motor was bad when I got the mower. I am lost as far as the wiring from the motor to the battery to the ignition switch. I put a different motor in the Exmark and i am having concerns on trying to run the mower without know the routing of the wires. Yes I did put a 27 hp Briggs commercial engine in the zero turn.
Any help would be appreciated.
 
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