Solenoid issues

[Jsmth86]

I have a 2008 precedent with alltrax 500, fsip speed and hd solenoid. I am on my 2nd solenoid and it is giving me issues. I can hear the solenoid click but when giving throttle the cart with slowly jerk and not move. It is acting like the solenoid is stuck. After a bit it will work or after I either hit it.

Any idea and help on why this is a common issue would be appreciated.

[R&TBabich]

Originally Posted by Jsmth86

I have a 2008 precedent with alltrax 500, fsip speed and hd solenoid. I am on my 2nd solenoid and it is giving me issues. I can hear the solenoid click but when giving throttle the cart with slowly jerk and not move. It is acting like the solenoid is stuck. After a bit it will work or after I either hit it. ....

If the solenoid clicks it has done it's job connecting the controller to the motor, assuming good contacts, etc.
The next thing the controller does is look at the foot pedal switch (MCOR) to determine how much current to provide to the motor.
It sounds like your MCOR variable switch is going.
With the Key Switch OFF try pumping the foot pedal 20 times or so.
This will swipe the MCOR contacts and maybe clean them a bit.
If there is an improvement the MCOR is probably getting old.
There is a 2nd switch in the MCOR to tell the controller the pedal has been pushed.
The wiper contact switch provides the pedal position.
There is a test procedure on the forum for the MCOR.
If you need an MCOR be sure to get the Made in Mexico ITW Switches version, not the one made in China.

[Jsmth86]

I had this issue last year, swapped the solenoid and did not have the issue again until now. I just replaced the mcor because I was having issues during acceleration. I do hear the solenoid click then off the throttle and back on the throttle. I don’t think my issue is the mcor - the cart (either in reverse or forward) from time to time will hesitate and will not move but inches at a time. If I give it a second or hit the top of the solenoid it will work but other times it won’t until it decides it wants to move.

[Tom47]

What amperage solenoid are you using? Your problem is again the solenoid. If it works when you tap on it, the contacts are burned or pitted. You need a 400 amp solenoid with your 500 amp controller.

Make sure you use both the coil diode and the main terminal diodes for the solenoid. A misstep during operation can damage your controller through current backfeed. Check the stickies for "both diodes".

Check with Scottyb for the best solenoid and diodes for your application.

[Jsmth86]

Got the 400amp solenoid from scottyb. I have the resisters and diodes installed. Just can’t understand why I am having issues.

[R&TBabich]

Originally Posted by Jsmth86

Got the 400amp solenoid from scottyb. I have the resisters and diodes installed. Just can’t understand why I am having issues.

With an Alltrax controller the resistor across the solenoid terminals is not used.
There is a large diode across the large connectors and a smaller one on the small connectors.
Check the wiring diagram from the Alltrax website.

[Jsmth86]

Interesting - I will have to double check to see if I have the resister across the top. If it is do you think this is what could be causing my problem. It seems that the solenoid is failing over time.

[Jake_Daddy]

You should have a resistor across the large terminals and a diode on the small ones. I wonder if your issue is more your throttle input.

[R&TBabich]

Originally Posted by Jake_Daddy

You should have a resistor across the large terminals and a diode on the small ones.....

I thought all Precedents were sepex systems, like our 2003.
Ours came with a resistor on the large solenoid posts, but when upgrading to an Alltrax controller it is replaced with a diode.

[Jake_Daddy]

I think you are correct on the sepex. If there is a resistor and it’s getting a bunch of regen current moving back through perhaps that could destroy a solenoid. I won’t commment further on this one as I am not as learned on those systems.