Fine for 12 years then one day it would not shut down, and then wouldn't key start ..installed new switch and new solenoid but no change.. SYMPTOMS and CHECKS ...> meter doesn't light, jump starts on Run or ROS, then runs with switch in any position, ROS position works, will shut down only with key off of ROS while engaging blade and reverse, meter checked wires from switch to solenoid and starter all intact, fuse good, mouse damage on fuel pump wire (repaired) but no where else seen, the 3 wire headlight cable open connector was cut off by mower ... NEED help diagnosing wiring diagram schematic checks for hidden faults please
I would start by testing your ignition switch , I've seen new ones that failed right out of the box, Test the switch with it on the bench with 12volts applied to the battery terminal and watch your meter / test light through all the positions.
First thing you need to check is do you have the correct key switch? Dozens of switches look the same, but are not interchangeable. Look at the back of the switches, side by side, and make sure each terminal is labeled the same.
#4
StarTech
In this Case it is a Delta 6900-49P switch. The 49 should moulded into the side of the switch.
If mouse damage was seen in one area, then double checking the wiring for intermittent short would be a good idea. Time to get out a multimeter and test light. Diagnosing an electrical problem from online ain’t easy and requires patience and steps on your part.
UPDATES & TESTS CHECKS...switch is original Husqv, though same make/break as StarTech shows, see my actual schematic attached... TESTED switch with G to negative and touched all contacts with battery positive, results: were all open circuits on Run, ROS and Start switch positions , but M and A1 tested closed circuit in the OFF switch position . Further notes... will not jump start with switch in off position.
Solenoid clicks in on bench test but will not activate when + contact hot wired on machine .
There's an open 3 wire harness leading to headlights, but Note diagram and common sense says only need 2 wires...where does the extra line go ?
#7
StarTech
Well it sounds like you have VOM so at the "B" terminal test for 12v. If not present then voltage is not making to the switch ie connection somewhere like a bad fuse holder.
If present then with ignition in any position other than off see if you have 12v on the "A" terminal. These checks are reference to ground. If not present it possible the one of the F56 terminals has failed. F56 terminal are spring loaded and this spring does break and makes loose contacts.
Most older mower have these F56 terminal but newer ones are switching to another style terminal. Mainly because they are cheaper for them to buy.
On the headlamp lead harness just make three wires are not touching anything including each other.
Any guess which one or two of my switch harness F56's it might be bad given my symptoms ?
If there broken where can I get a replacement, and could I rig another type of clip in ?
THANKS very much for your help !!
#11
StarTech
Sorry but my crystal ball got broken last week and I was informed yesterday its too old to repair. You going have to look for yourself.
First prove it's the switch then either get a replacement or re wire if necessary , apply 12 volts to the selonoid terminal where the ignition switch hooks up , if it kicks in , you have a bad switch or wire then go from there
Any starter switch will probably work , all you need is 12 volts supply then 12 volts in the start position , you'll need to have a kill wire as well but get there one at a time .
Problem SOLVED..this should be a Sticky on how to persistently follow the symptomatic clues to solve an obscure problem when all parts check good, and your readings, specs and schematics don't help.... SOLUTION : follow and investigate the observations that don't make sense , in my case : 1). that the solenoid didn't kick in when hot wired and 2). the 3 wire cable to headlights that needs only 2 wires ...
First I found the primary + wire to solenoid was hot, and the negative side was not grounded in any key position and read hot when read back to switch ..why the solenoid when hot wired wouldn't kick in...so I needed to find a ground fix for the solenoid negative ..which curiously enough I had an extra ground wire in that head light cable to solve...so following the clues I connected each of the wires to ground and BINGO the spare black wire to the headlights is actually the ground for the solenoid and the problem was solved and now everything works again.
OBSERVATION..> you can't always blindly follow the factory specs and diagrams, e.g. why would you physically wire a ground six feet away when the needed connection is only 6 inches away ??
To check the connectors, slide the plug off the ign sw enough so you can see the terminals. Check the continuity between the wire side of the plug and the terminal it connects to. Should be 0 ohms. On inline connectors. push your probes into the connections from each side and verify 0 ohms. If you find a bad connection, try pushing the wire into the connector and see if it changes. Not only do the connections slide out if the tab is broke, but also become corroded. Clean with a small wire brush and carb cleaner.
So, why didn't you fix the harness damage first? Seems like an obvious starting point, and it being cut concurrent to this problem seems like it would be screaming at you . . . (or did I miss something?)
#19
doug9694
Perhaps the new switch is defective or the wiring is bad. The kill from the reverse is working so tie into that wire with another toggle or push button switch back to ground. Or get a wiring diagram for your model # and track and test each wire and component.
