2004 CC Precedent MCOR problem?????

[Keith]

Matti,
I found an old thread that DUS started back on June 4, 2009 that pretty much describes the exact same problem I am finding with my 2004 48V Precedent. I have already installed a new solenoid and OBC, but the sporadic failure to run and/or keep running persists. Today I jacked the cart up and it's sitting on blocks to make testing easier. I have removed the floor mat and belly pan cover to access the MCOR wiring and pin plugs. Like DUS described in his thread the MCOR appears to be a sealed unit.
Question #1..........Is there a way to test out the MCOR? (like sticking a needle in the wire(s) to test for voltage back to the controller)

Question #2..........Can you reccommend a site where I can purchase a new MCOR?

Thank you in advance for your help.

[gaminde]

If you do not mind me answering download the schematic from this site it should show the colors of the wires at the MCOR and what they are used for, you have 1 switch and a rheostat in the MCOR. I think 5 wires.

[Keith]

Thanks for responding Gaminde. You are correct, there are two pin plug connectors on the MCOR unit. Looking down into the well the top plug has a Blue and a Green wire. The bottom plug has three wires, Yellow, Purple, and White/Black. Thanks again for your help. Keith from Minnesota

[gaminde]

Most likely blue and green jump together will turn on solenoid.

[Keith]

Thanks, I'll test it tomorrow and post the results.

[Keith]

This morning, with the cart on blocks I ran the cart with normal starting process. I pressed the accelerator with it in the forward mode. The cart ran for three cycles of letting off and starting it again before it failed to run. As gamandi suggested, I jumpered the Blue & Green wires that control the micro switch in the MCOR unit. With the jumper in place the cart ran great. I tested in forward and reverse for several cycles before removing it from the blocks and running it around the park. I plan on running it for couple of days with the jumper in place to make sure the problem is resolved. Gamindi, do see any problems with this plan? Again, thank you so much for help!!! Keith

[gaminde]

UUMMMMM
Let me answer this way,
do you have any kids around,
does the solenoid release when key switch is turned off,
will you pull the key out when your not riding it

?????????????????????????????????????????????????? ?????

[Keith]

No kids around that would have access to the cart. I will remove the key when I'm not using it.
With the key in the "off" position I'm not showing any voltage at the solenoid. When the key is "on" and I press the accelerator to go I can hear the solenoid kick in and the cart runs without a problem.
I am pretty sure the MCOR OEM replacement part number is 102528501/103327901. I do need to verify this part number before I order a new one.

[gaminde]

I'm a little confused ??
if mcor switch is jumped then the solenoid should be engaged at all times the key is on, your saying that when you push the pedal the solenoid engages.

[Keith]

I'll hook the meter up to the main solenoid terminals and check out again to make sure this is what is happening. I'll post the test results.

[gaminde]

Not main terminals you want to hook to small coil terminals, that's why the meter reads 0 volts when solenoid is activated.

[Keith]

I just completed a quick test. Your right, I'm getting 50.3 volts accross the two small terminals when I press the peddle. Zero voltage when I let off the peddle. During this process I put my hand on the bottom to the solenoid and when I pressed the peddle I can feel it kick in and the cart will go with no problems. When I let completly off the peddle the solenoid feels like it is dropping out. I hope this explains better what is happening.
For my jumper link I used a 2" piece of stainless steel wire and bent it in "U" shape so it would fit inside the plug that is disconnected from the MCOR. I used electrical tape to cover the jumper and plug and left it lay in the well by the MCOR.

[gaminde]

Your not doing something right, if you jumper the MCOR switch then it is on all the time, if its not jumped then its going to turn on and off with pedal press it can't do both.

You may have had dirty connection and by messing around its better so spray out all the connections with spray cleaner.

[Keith]

Gaminde, thank you again for your patience and sharing your knowledge with me on this MCOR problem.
Lets back up to where I installed the jumper accross the "blue" & "green" wire plug that is removed from the MCOR. As I see it, we are bypassing the MCOR limit switch. What I am finding is that with the key turned "off", run/tow switch is in "run" I am "not" detecting voltage at the solenoid (small terminals). With the key turned "on" I am not finding voltage when I test across the small terminals on the solenoid. However, when I test the terminal with the "blue" wire to ground I get a 49.9 volt reading. Okay, then I tested for voltage on pin-6 (green wire) on the speed controller and found the same voltage (49.9 volts) when tested to ground. That tells me that the jumper is in fact in place and is working correctly. My next step was to hook up the meter leads to the solenoid small terminals to find that when the cart is in "forward" or "reverse" and the accelerater pedal is pressed down that the solenoid is kicking in (49.9 volts) and the cart will run without a problem. When the pedal is released back to the off position the solenoid drops out and the meter is reading zero voltage.
The question I have is do you think the Curtis motor speed controller is effected one way or the other by having the "green" wire on pin #6 being "hot" with the key turned "on" and the jumper in place. To me it doesn't seem to matter because it is not completing the circuit and closing in the solenoid until the pedal is pushed down?

[gaminde]

its not acting like I would have expected, so i looked at the schematic.

green wire is pin 6 at controller
Blue wire is hot wire (from run/tow to key to blue)
controller pin 12 grounds the solenoid

put your ohm meter on the mcor contacts that go to the green blue wires actuate the pedal and see if you get a reading when pushed and off when released. looks like the switch is bad in the mcor.

The question I have is do you think the Curtis motor speed controller is effected one way or the other by having the "green" wire on pin #6 being "hot" with the key turned "on" and the jumper in place. To me it doesn't seem to matter because it is not completing the circuit and closing in the solenoid until the pedal is pushed down? 21 hours ago 02:46 PM

That is what the MCOR switch does. If you get a new MCOR I would like the old one and will pay for shipping I would like to see if rebuilding them is possable.

[Keith]

I like your reccommended plan and I agree with you that I need to verify that the MCOR limit switch is failing to close consistantly when the pedal is pushed. I am almost 100% sure the limitswitch will fail the ohm test and I will need to replace it.

Yes, when I get a new one and install it I will be glad to work with you to get it shipped out to you for disection & inspection. Keith

[Keith]

Today I removed the brake peddle & accelerator housing group to check things out and gain better access for ohm testing the MCOR limit switch. Findings: The limit switch is definitly the "Somoking Gun" failure I've been looking for. I plan on getting new one ordered today. (cartbarn.com for $118.00)

Gamindi; When I get the new MCOR installed (sometime next week) we can finalize the plan to get the "failed" MCOR shipped out you.

[gaminde]

Excellent on both accounts, Its a good feeling to confirm a problem when troubleshooting.