Bad Ignition Switch?

[stevewm]

I have a 2005 3510 2ith about 500 hours with what I believe to be a bad ignition switch.

Got on the tractor this AM, turned the key and waited for the glow plugs to time out. Correct lights were on and fuel pump was ticking away as normal. Turned the key to start and engine started to turn over for one second then stopped. Status lights went to dim. Thinking Ihad a battery issue, I cleaned and tightened the terminals, and tried again. Had lights and fuel pump but got nothing when I went to start and lights again dimmed. Tried cleaning and tightening terminals again and checked that chassis ground was good. This time the lights came on and that was about it. Checked the battery at 13.1 volts. Checked the fuses in the small panel forward of the clutch and they all looked good. Took ones directly in the starting circuit out and checked them okay with ohmmeter. All connections seemed tight on starter and alternator. Only other common point for the electrical system is the ignition switch. Have removed it and did some bench testing. There are seven connectors in its little wiring harness. Three show 0 ohms between them and the lead I assume to be the power in - heavier gage and in a connector by itself. Waiting for help to see what is happening with the other five connectors when the key is moved to the start position nor have I traces any other leads on the tractor.

It started and ran normally yesterday afternoon.

Any other ideas?

Steve in Central TX

 

[Stimw]

First I would check all the starter lockouts/Neutral switches to make sure everything is in neutral.
Cycle the shifters and PTO lever to be sure they are working.
After that I would try jumping the starter directly MAKING SURE IT IS IN NEUTRAL FIRST.

 

[stevewm]

Did everything but jumping the starter. Normally when I turn the switch on, the indicator lights on the instrument panel come on regardless of the lockout switches. There are three lights total, one for glow plug timeout, one for alternator power, and the other for low oil pressure as I recall. The first time around the lights were on and fuel pump working, everything quit when I tried the starter, 2nd time had lights and pump and again, lights went out when I hit the starter. Third try, no panel lights, nothing. Couldn't get head/tail lights either. I need to put the battery back in and check if there is power to the starter/ignition switch.

 

[MikeInEburg]

Use another battery and jumper cables to confirm battery. 13v resting is inconclusive.

 

[stevewm]

I'll give that a try. Right now the battery is in the shop. I have a handheld load tester that is reasonably useful and it gives an indication the battery is good after putting a load on it. I also have a good battery minder and conditioner that I have used on marine and RV batteries hooked up to it. The self test shows it is good and when I try to condition/charge it, the charger goes almost immediately into the maintenance float mode. On the other hand the battery is 4 yrs old and battery issues have bitten me in the past.

 

[SPYDERLK]

Check the crimp connections at each end of both batt cables. Sounds like one is going bad. Try the crank then feel for heat.
,,,You can also check the V loss under load with your voltmeter.

 

[stevewm]

A bit misty outside, tractor is just outside my shop and not under shelter. This AM I reconnected the battery and checked voltage at the ignition switch. Got 12.7 volts. Turned on switch and got lights and fuel pump. Head and tail lights work as well. Turned to start position, heard a loud click that sounded like under the instrument cluster, then lights and fuel pump went out. Check voltage to ignition switch, still 12.7 volts. Reconnected, no lights. going to try to jump to starter from batt when mist stops. I have a feeling that if I disconnect the battery and reconnect, I will get lights and fuel pump again until I try to start. Seems like something in the starter circuit is shorting and driving the entire electrical past the starter/ignition switch to ground so nothing gets past that point. Wish I had a schematic bit all I have is just diagrams with no color coding for wiring.

 

[stevewm]

Appears humble pie is in a future menu for me. The tractor is in trees and in a bad place to get another vehicle in but I managed to wiggle my Tundra in close enough to hook some battery cables up. Problem solved. With battery jumped, the tractor would crank a little and the lights stayed on as long as key was on. Headed to Interstate Batteries to pick up a new one. I did try to put a load on the old battery before hand and voltage would drop tp under 2V, recovering back to 12V each time but apparently not enough amps to energize the circuits in the tractor for more than one shot.

I did do some searching on the web for 3510 starting problems and apparently relays are at fault much of the time but didn't see any where the electrics went totally dead - not even enough amps to turn a ight bulb even though 12V was showing on the meter. I did follow two different troubleshooting charts and both pointed to the ignition/start switch so that is what set me off in that direction.

Thanks for the help.

 

[LincTex]

Steve W M, where did you get a wiring diagram? Where are the relays located?

I had to add a jumper with a momentary switch to activate my starter solenoid on my 2005 3510i