Need help with 95 medalist

[JohnnieB]

Originally Posted by DJGCWB

Question about checking the B- and M- on the controller. Just touch one lead to each post on the controller? It won't matter which is positive or negative? Don't check each one individually with my negative lead grounded to the main pack negative?

It doesn't really matter, but if you put the Negative test lead (Black) on the controller's B- terminal and Positive test lead (Red) on the controller's M- terminal, you will read a positive voltage.

[DJGCWB]

I'm gonna go ahead check and see how it's looking.

[DJGCWB]

Originally Posted by JohnnieB

It doesn't really matter, but if you put the Negative test lead (Black) on the controller's B- terminal and Positive test lead (Red) on the controller's M- terminal, you will read a positive voltage.

Pack voltage: 38.6
For the next two key on, in forward and depressed accelerator to engage solenoid:
Pin-1 Small red wire voltage from solenoid to controller: 38.5
Voltage across B- and M- on controller:
36.6 prior to pushing pedal to engage solenoid
Dropped to 17.9 after solenoid engaged.

[DJGCWB]

It's been 12 hrs and the pack is still at 38.6 volts

[JohnnieB]

Originally Posted by DJGCWB

Pack voltage: 38.6
For the next two key on, in forward and depressed accelerator to engage solenoid:
1. Pin-1 Small red wire voltage from solenoid to controller: 38.5

2. Voltage across B- and M- on controller:
36.6 prior to pushing pedal to engage solenoid

3. Dropped to 17.9 after solenoid engaged.

1.

2. If there is a pre-charge resistor installed across the solenoid's large terminals, this is a normal reading before the solenoid clicks.

3. Abnormal reading. This should go to full pack voltage the moment solenoid clicks, when pedal is pushed just far enough to make solenoid click.

Three possibilities that can cause it to be 17.9V.
A. Solenoid contacts are mot making contact.
B. Pack voltage is dropping to 17.9V.
C. Pedal was pushed about halfway down when reading was made

[DJGCWB]

Originally Posted by JohnnieB

1.

2. If there is a pre-charge resistor installed across the solenoid's large terminals, this is a normal reading before the solenoid clicks.

3. Abnormal reading. This should go to full pack voltage the moment solenoid clicks, when pedal is pushed just far enough to make solenoid click.

Three possibilities that can cause it to be 17.9V.
A. Solenoid contacts are mot making contact.
B. Pack voltage is dropping to 17.9V.
C. Pedal was pushed about halfway down when reading was made

Ok. So I made very sure to just apply enough pressure to engage the solenoid and no further with the accelerator. I guess I need to check pack voltage while pressing the accelerator. Correct?

[JohnnieB]

Originally Posted by DJGCWB

Ok. So I made very sure to just apply enough pressure to engage the solenoid and no further with the accelerator. I guess I need to check pack voltage while pressing the accelerator. Correct?

Yes, there is a possibility the pack voltage is dropping. Battery failing under load.

I'm more inclined to suspect the solenoid contacts are bad. If it was the original OEM solenoid, the contacts are only rated for 85A, so it was marginal at best after 20 years of use and the new batteries might have nailed the final nail in the coffin.

[DJGCWB]

Ok so what is acceptable for the pack to drop to under load and what would indicate battery failing under load?
If the pack is ok under load then the next step would be replace the solenoid?

[JohnnieB]

Originally Posted by DJGCWB

Ok so what is acceptable for the pack to drop to under load and what would indicate battery failing under load?
If the pack is ok under load then the next step would be replace the solenoid?

With a new set of 6V - 232AH batteries, about 0.1V per 100A of current for the batteries themselves and about another 0.1V per 100A for the amp delivery system, or about 0.2V total per 100A for current flow.

Your motor isn't spinning and nothing is smoking, so you aren't drawing anywhere near a 100A, so the pack voltage shouldn't be dropping more than 0.2V at most.

If the pack voltage stay close to the same, replace the solenoid.

[DJGCWB]

Originally Posted by JohnnieB

With a new set of 6V - 232AH batteries, about 0.1V per 100A of current for the batteries themselves and about another 0.1V per 100A for the amp delivery system, or about 0.2V total per 100A for current flow.



Your motor isn't spinning and nothing is smoking, so you aren't drawing anywhere near a 100A, so the pack voltage shouldn't be dropping more than 0.2V at most.



If the pack voltage stay close to the same, replace the solenoid.

10-4 good buddy!