17CRCACA009 PTO problem

[StarTech]

Okay guys here for you to figure the root cause. Now I have resolved this problem but just like to see if any of you can figure it out.

Problem report: PTO randomly shuts off while mowing. Having to cycle PTO switch to get it back operating. And sometimes it takes multiple cycles.

Additional Info: Found that during the duplication of the problem, it gets worst the longer you mow.

Now the guessing starts....

 

[ILENGINE]

My first guess would be clutch air gap too wide, but that could just be a symptom from a host of other issues, like faulty pto switch, faulty mow in reverse system, low charge/battery voltage, or faulty seat switch,

 

[Rivets]

My first guess is loose ground to chassis connection. Second wound be frayed wire between the clutch and PTO switch causing a short. As IL stated, could be a symptom, but not enough info.

 

[StarTech]

Well clutch is fine, no frayed wires, loose ground, or loose connections. Seat switch good and new battery.

Hint it is in the mow reverse system and it is a thermal problem. Now see if you can pin point it. The both lap bar switches are good, Mow in reverse control panel is good, Ignition switch good. I actually bypassed the reverse control panel and the lap bar switched an it still acted up. I even completely disabled the mow in reverse system by cutting the ground wire and it still acted up.

By the way the component that failed is not even listed in the IPL. Now the wiring schematic does shows it but I tried to get Cub Cadet to send me a diagram but their brains don't work as all they sent was a component location diagram from the IPL which of course is of no help at all.

 

[ILENGINE]

Does it have a relay that MTD claims that doesn't exist.

 

[Rivets]

Could it be this PTO relay?

Cub Cadet 925-04164 Relay Z RZT​

 

[StarTech]

BINGO, IL that non-exsistant relay....Burned contacts causing it to over heat. And Cub Cadet tried to get me to buy a complete wiring harness to replace a $2-$5 relay.

And no Rivets that not the relay. It is MTD PN 925-1648 which crosses to CM-1-R-12V.

Here is a list of all the available crosses I have found so far.

 

[Rivets]

I picked the wrong relay, but was close.

 

[StarTech]

I picked the wrong relay, but was close.

And I should pat you on the head for not biting my hands...Yes you where on the right track. It was kinda strange a resting relay was giving a problem until understand that 3-5 amps is flowing through the contacts.

Finding where they hid it was sorta a challenge but not hard once you know where they had put it. Too bad MTD and Cub wants to be so secretive about it. Just getting the wiring schematic is like pulling eye teeth. Finally found a company that was willing to part with the info.

I learned a lot more than I needed for the repair but now know how take the RMC module out of the circuit and still have the safety working as intend but it no longer has a over ride function. The override really is not need as very few of my customers mow in full reverse.