Export thread

Model 13B9A1CS010 ser#1D108H40176 115hours Won't turn over. When starter button is pressed, LCD shows voltage for ≈2 seconds, then a barely audible relay click in the keyswitch and hum (fuel pump?) and showing hour meter, then nothing changes until timeout. No (louder) click from starter solenoid. If I don't push the brake pedal, LCD shows "br". if I engage the PTO, the LCD show "pto". If I'm not on the seat, the LCD shows voltage and nothing else happens, so the panel is recognizing those switches. Last year, I pulled the dashboard off and cleaned a molex type connector that was near the keyswitch panel, and got it to start. This season, I pulled & cleaned 2 connectors on the right side of the engine, and got it to start. Today, cleaned those again and 2 more on the left side of the engine, and nothing. The mower mechanically works fine, so I hate to scrap it over bad wiring components. Is there any info available on how to make the wiring harness more "old-school" ?

This is the problem. Cub/MTD has not released any info on the wiring to us non dealers. I called my tech support at RBI and Mike is having to reach out to his sources to see if any info is available. But as of right now most of us are in dark just as you are.

Keeping things so secret is hard on all of us that are independent shops that are sometimes have better techs than the dealers.

Well at least I got a X90 engine manual out of this. Now trying to find the diagram for mower side.

Okay, looking the engine wiring schematic the starter not engaging is on the mower side. If not a bad connection it is probably the module that you use to start the start up sequence. So basically it not an engine problem.

Looking at it again this morning, I was going to remove the solenoid to bench test it and thought the ground terminal pulled off a little too easy. I squeezed/deformed the female harness connector a little so it would push on the solenoid tab a little tighter, and the mower started. I didn't think about the solenoid too much because of the time delay listening to the keyswitch, but now I realize that delay is probably to give the fuel pump some time to pressure up. I wish they would have put the solenoid under the gas tank right behind the engine, so terminals could be probed in place under power. I'm sending schematics that I got during one of the other times I was working on it. I think the pdf is the appropriate one that has the fuel pump for EFI. The jpg I'm not sure about. I think I still might rewire from scratch as a winter project. Thx for your help, much appreciated.

Okay the schematic can't be for your mower. As there is a little more involved connecting to engine. On top that it is a keyswitch version.

Here is the X90 engine wiring diagram. As you can see there is two interconnects from the engine to mower. But it should be possible to convert to keyswitch but it will take some experimentation.

StarTech said:

Okay the schematic can't be for your mower. As there is a little more involved connecting to engine. On top that it is a keyswitch version.

Here is the X90 engine wiring diagram. As you can see there is two interconnects from the engine to mower. But it should be possible to convert to keyswitch but it will take some experimentation.
View attachment 69741

Click to expand...

The mower refused to start for the 6th time, and the formerly successful cleaning of fittings didn't help. The mower is mechanically in good shape so I didn't want to scrap it over a shoddy wiring harness, so I installed an external start button. Tapped into a fused red wire near the main +battery eyelet, then to a pushbutton switch n-o terminal, then to the solenoid tab where it replaced the hot lead from the wiring harness. When the keypad button is pressed, the efi fuel pump runs for ≈4 seconds. During that time, pressing the external pushbutton starts the mower. Killing the engine with the keyswitch or the seat switch works as before.

Hello R.,

Shop around for a product called DeoxIt D5. It is an effective contact cleaner that leaves a protective, yet conductive film on the pin contacts.

Go through and clean every connection on the machine the apply this stuff.

The old method of applying silicone compound has caused more problems than it has fixed over the years. It keeps moisture out, but it also insulates pin contacts which affects proper conductivity.