Help with solenoid wiring - Medalist

[DubK]

Also, I did find a burnt up looking connection on the key switch just now.

[JohnnieB]

Originally Posted by DubK

I get 38 volts on the small red + terminal no matter if the gas is pressed or not. Solenoid doesn't click at all when gas is pushed. Constant 38 no matter what. Does this mean bad switch? Only switch I have yet to change is the key switch

The only time there should be 38V on the red wire to the solenoid coil is when four sets of switch contacts are closed.
1. Reed switch in charge receptacle
2. MS-2 on F/R assembly
3. Key switch
4. Pedal switch (MS-3)

Attached is a schematic of a series drive with the solenoid activation circuit highlighted.

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The burnt crimp-on connector is in the 12V lighting circuit, so it shouldn't effect the drive system.

[DubK]

Ok good to know. Mine doesn't have a reed switch that I can see. Unless it's hidden inside the charge receptacle but there's no red wire coming out of there, and yesterday I changed out MS2 and MS3 to new switches. I ordered a key switch today it should be here tomorrow. I'll report back once I install it. But this means the solenoid is not bad, correct?

[JohnnieB]

Don't know one way or the other about the solenoid.

[DubK]

Ok thanks for the help! Soon as I get the new key switch in if it still doesn't work I'm going to order a new solenoid. Might as well keep throwing parts at it until it works

[DubK]

Well no luck today either. I was pretty certain I had a bad switch or two. I changed MS-2, MS-3, and the key switch out. (No reed switch on this cart). Still won't go. No click from solenoid or anything. Tired of throwing money at it and nothing fixing the problem. But I guess I will have to order a new solenoid. It already has a brand new HD f&r, new 350 amp controller, barely used SW180 solenoid from my other cart, and all new 2g cables. Volt readings are where they should be minus the solenoid not clicking. If a new solenoid doesn't fix the problem I'm about ready to give up!

[DubK]

Alright so today I installed the brand new Curtis SW180 solenoid and it still won't work. No solenoid click or anything. So far I have installed a new HD f/r switch, new solenoid, refurbished 350 amp controller, and all 2g cables, and I changed all of the microswitches out to brand new ones (pedal switch, key switch) since that's what Johnnyb thought it might be so. Couple months ago I installed a new ITS in the pedal box as well. I don't know what to do at this point. Everything worked fine before I took it apart to put all the new parts and cables on it.

[DubK]

Sigh. Now I ran into a new problem. I was tracing the solenoid activation schematic checking voltages to figure out why the solenoid won't activate. Well I just installed a new key switch when I changed all of my switches out, and as soon I put the positive test lead to the blue wire it sparked and burnt it up. What would cause this? Negative probe was on battery negative which is what I thought the proper way is to test things. Now do I need to buy another key switch?

Also, the voltage reducer is pretty warm now and I have not noticed this before. Is this normal? I unhooked it to be safe for now.

[JohnnieB]

Looks like the arc burn is on one of the two blue wires with white stripes and the picture of the old keyswitch that showed a burnt connector was also on one of the Blue/White wires. The blue/white wires feed 12V to the 12V accessories and are not part of the 36V control circuit for the series drive. You mentioned the voltage reducer is getting warm, that may also be another indicator the 12V accessory circuit is sick, but it is not associated with the solenoid not clicking.

Unless your meter was set up to measure Amps or Ohms or diodes, it shouldn't have caused an arc. The test probe tip shorting between the 36V circuit to the 36V circuit is another possibility.

Voltage measurements are typically made with the black test lead connected to the battery pack's main negative terminal (B-). A DVM's impedance is typically a Megohm or more, so arcing through the meter is highly unlikely.

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Let's simplify things and eliminate all the extraneous stuff from the solenoid coil circuit.

Disconnect the Voltage reducer.
Disconnect the two blue/white wires from the keyswitch.
Disconnect the red wire from the keyswitch.
Remove the diode from the solenoid's small terminals.
Remover the pre-charge resistor from the solenoid's large terminals.

Now measure the voltage on the red jumper wire between the two microswitches on the F/R assembly.

How much voltage did you measure?

[DubK]

Ok I'm going to order a new key switch so I won't be using one with a burnt connection. But in the mean time I will save all the 12 volt stuff for later and focus on this solenoid. Thanks for simplifying it. I'll get on this tomorrow and get those readings when I get some more daylight and get back to you.