Electrical / Starting Problem with Husqvarna YTH21K46

[mwpowell]

I have a Husqvarna YTH21K46 mower with a Kohler Engine (SV610-0212). I'm attempting to troubleshoot problem starting the mower which is becoming very time consuming and expensive. In short, I have replaced the battery, solenoid switch and starter motor. However, none of these have resolved my problem.

The mower will not turn over at all. They solenoid switch sounds as though it is engaging (repeated clicks when I turn the key) however, when I measure the voltage from the solenoid switch to the starter, I only get between 6 and 7 volts. However, I am getting between 12.4 and 12.8 volts from the battery to the solenoid. I see one fuse that is intact, but there could be others that I don't know about.

What could be causing the voltage drop from the solenoid to the starter?


Thanks in advance.

 

[SeniorCitizen]

What could be causing the voltage drop from the solenoid to the starter?


Thanks in advance.

Bad wire or connection. Try it with a jumper cable connected from the solenoid out terminal wire end to the starter wire end.

 

[Rivets]

Here is a procedure for troubleshooting electrical problems. As SandBur said, check electrical connections first.



Electrical* problems can be very easy or very difficult, depending on four things.
1. * How well you understand basic electricity.
2. *What tools you have and know how to use.
3. *How well you follow directions.
4. *You don't overlook or assume anything and verify everything.

Remember we cannot see what you are doing. *You are our eyes, ears and fingers in solving this problem. *You must be as accurate as you can when you report back. *The two basic tools we will ask you to use are a test light and a multi-meter. *If you have an assistant when going through these tests it would be very helpful. *These steps work the best when done in order, so please don't jump around. *Now let's solve this problem.

First, check the fuse(s), check battery connections for corrosion (clean if necessary) and *voltage - above 12.5 volts should be good.*

Second, check for power from the battery to one of the large terminals on the solenoid. *One of the wires is connected directly to the battery and has power all the time so one of the large terminals should light a test light or show 12 volts on a meter at all times.*

Third, *check for power at the small terminal of the solenoid while depressing the clutch/brake pedal and holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch). If your solenoid is a four wire solenoid, check both small wire terminals as one is ground and the other is power from the ignition switch. *If your solenoid is a three wire solenoid, make sure the solenoid body is not corroded where it bolts to the chassis of the mower as this is your ground path back to the battery. *If in doubt, remove the solenoid and clean the mounting area down to bare metal. *If there is no power to the small terminal then your problem is most likely a safety switch, ignition switch or in the wiring.*

Fourth, check for power on the other large terminal of the solenoid while holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch).*

Fifth, check for power at the starter while holding the key in the start position (assistant again).*

Sixth, check your ground circuit back to the battery.

After you have gone through each of the above steps, let us know what happened when you did each step. *At that point we will have great info to tell you how to proceed. *Remember you are our eyes, ears, and fingers, so please be as accurate as possible.

Be as specific as possible with voltage readings as this will help diagnose your problem quicker. *If you do not know how to perform the above checks, just ask and I will try to guide you through it. *Youtube also has some videos and as you know a picture is worth a thousand words.

 

[mwpowell]

First, check the fuse(s), check battery connections for corrosion (clean if necessary) and *voltage - above 12.5 volts should be good.*

All connections look clean and there is no corrosion at any of the connection points. I replaced the battery and can confirm that the fuse is good and the voltage is above 12.5 volts at the battery.

Second, check for power from the battery to one of the large terminals on the solenoid. *One of the wires is connected directly to the battery and has power all the time so one of the large terminals should light a test light or show 12 volts on a meter at all times.*

I am also getting above 12.5 volts at the battery side of the large terminals on the solenoid. As a matter of course I replaced the solenoid as well.

Third, *check for power at the small terminal of the solenoid while depressing the clutch/brake pedal and holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch). If your solenoid is a four wire solenoid, check both small wire terminals as one is ground and the other is power from the ignition switch. *If your solenoid is a three wire solenoid, make sure the solenoid body is not corroded where it bolts to the chassis of the mower as this is your ground path back to the battery. *If in doubt, remove the solenoid and clean the mounting area down to bare metal. *If there is no power to the small terminal then your problem is most likely a safety switch, ignition switch or in the wiring.*

I confirmed this and also replaced the solenoid.

Fourth, check for power on the other large terminal of the solenoid while holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch).*

I only get between 6 - 7 volts on the other large terminal of the solenoid (towards the starter).

Fifth, check for power at the starter while holding the key in the start position (assistant again).*

Same as above, I get between 6 - 7 volts.

Sixth, check your ground circuit back to the battery.

How do I check the ground circuit? Also, could this have something to do with the ignition unit which I see on the side of the motor?

The starter does not attempt to turn the engine over at all. I hear the solenoid firing, but the starter does not move.


Mike

 

[Rivets]

If you are only getting 6-7V on the starter side of the solenoid, that tell me that the solenoid is bad. You dais that you replaced the solenoid. If you have a three post solenoid, check to see if you have a good ground between the solenoid base and the chassis. Also, check that your have 0.0 Ohms between the base of the solenoid and battery negative terminal. If you have a four post solenoid, do you have a good connect (0 Ohms) from the fourth post to battery ground. At test 4, you should have a minimum of 12.6V. You may have a bad solenoid, even if it is new.

 

[mwpowell]

You may have a bad solenoid, even if it is new.

Possible, but extremely unlikely. Is there a more likely culprit than two bad solenoids?

Also, how do I test the ground circuit back to the battery?

 

[Rivets]

Do you have a three or four post terminal solenoid? Three post, solenoid base to battery negative, 0 Ohms. Four post, ground post to battery negative, 0 Ohms.

If you have 12V on the battery side of the solenoid and only 6-7 V on the starter side when the key is turn to start, that means that the contacts inside the solenoid are not doing want they should.

 

[mwpowell]

What could be causing the voltage drop from the solenoid to the starter?

After much toil, I was able to pinpoint the rather simple solution to the voltage drop. I checked each of the safety switches (clutch, seat and mower blade switches) - all three were perfectly fine. I checked the voltage again at the solenoid and it consistently drops on the starter motor side of the solenoid.

The only other circuits were the three safety switches mentioned above. Although the wires could be a problem, this was unlikely. I removed and cleaned the wire leading from the solenoid to the starter. Once I re-seated the clean wire, I was able to get 12 volts on the starter side of the solenoid.

The mower started like a champ and is running fine.

For the benefit of others here, cleaning and reconnecting the wiring would have saved myself a lot of headache. Check these simple things first before chasing problems with the switches.

 

[Rivets]

Congratulations but I have to say it. I think SandBur posted to check the connections in post #2.

 

[mwpowell]

Congratulations but I have to say it. I think SandBur posted to check the connections in post #2.

Yes, I should have done this first rather than....

First, check the fuse(s), check battery connections for corrosion (clean if necessary) and *voltage - above 12.5 volts should be good.*

Second, check for power from the battery to one of the large terminals on the solenoid. *One of the wires is connected directly to the battery and has power all the time so one of the large terminals should light a test light or show 12 volts on a meter at all times.*

Third, *check for power at the small terminal of the solenoid while depressing the clutch/brake pedal and holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch). If your solenoid is a four wire solenoid, check both small wire terminals as one is ground and the other is power from the ignition switch. *If your solenoid is a three wire solenoid, make sure the solenoid body is not corroded where it bolts to the chassis of the mower as this is your ground path back to the battery. *If in doubt, remove the solenoid and clean the mounting area down to bare metal. *If there is no power to the small terminal then your problem is most likely a safety switch, ignition switch or in the wiring.*

Fourth, check for power on the other large terminal of the solenoid while holding the key in the start position (you may need an assistant to sit in the seat to override the safety switch).*

Fifth, check for power at the starter while holding the key in the start position (assistant again).*

Sixth, check your ground circuit back to the battery.

It turns out that none of that helped at all. Next time I'll just listen to SandBur. Many thanks SandBur.