Minn Kota 3hp...anyone have one?

[sam am I]

I put + probe on battery +, and negative probe on the bottom of the board, right around where the black arrow is in that picture. I did have to puncture the layer of laquer on the bottom of the board. Showed 12.48 volts, which is what the battery shows with meter hooked directly to battery.

Then the red battery wire is open (or not connected properly to) somewhere from the battery + post and the soldered spade connector (battery +) seen in the pic's below, should be just a wire between your probes......

I'll try the light bulb test. Guess this would work with a regular test light, right?

*Yes, it should, assume you'd use standard incandescent type.


*Not going to work until we have the relays clicking when pinching the flex pot.


Lets try this approach............Place neg meter probe on battery - and meter probe + on same foil (battery+ soldered spades/black arrow foil again), what now?

 

[jeepwm69]

Neg probe on neg post and pos probe on bottom foily stuff gets nothing.

 

[jeepwm69]

Super simple test, eliminating all else..........Use a 12V battery connected just to battery + and battery - connectors (J3, J4) shown just above and leave the white wires disconnected. Then pinch the face of the flex over the dark area's (described several posts above).

This turns on the board (you'll hear both the relays click, relays turning on then turns on U2/UC3842).

If that works...

Now hook up a 12V light bulb (car tail or brake bulb) to white wires (motor+ and motor-), slide fingers in rotation while pinching or simply let off and pinch in different dark areas, the bulb will vary in intensity (PWM)..........

Something else of interest.... All four of the white wires coming off the board show 12 V with a negative probe on my meter connected to the negative post of the battery.

The picture you have above that has those labeled shows two positive and two negative.

 

[sam am I]

Neg probe on neg post and pos probe on bottom foily stuff gets nothing.

To a very basic setup then, just the board by itself and seen below (nothing attached to it), one 12V battery and two jumper wires needed ..........


Grab the 12V battery that has nothing on either of the posts and grab the two 2' lengths of wire (optionally with alligator clips on ends and one wire is red and one wire is black)

Referring to the pic below of the board, nothing connected to the spades or the white wires,


Now.........

1) Run a single wire (the optional red) directly from the battery's positive post directly to the J3 (battery +) spade connector seen above.

2) Run a single wire (the optional black) directly from the battery's negative post directly to the J4 (ground/battery-) spade connector seen above.

Check Voltage.........

3) Connect the meter's negative probe - directly to battery negative post.

4) Using the meter's positive probe +, now probe/touch the J3 (battery +) spade connector seen above where the red wire directly attached to the J3 spade......12V?

 

[sam am I]

Something else of interest.... All four of the white wires coming off the board show 12 V with a negative probe on my meter connected to the negative post of the battery.

The picture you have above that has those labeled shows two positive and two negative.

Not to worry about that right now, lets get ya setup above first

 

[jeepwm69]

To a very basic setup then, just the board by itself and seen below (nothing attached to it), one 12V battery and two jumper wires needed ..........


Grab the 12V battery that has nothing on either of the posts and grab the two 2' lengths of wire (optionally with alligator clips on ends and one wire is red and one wire is black)

Referring to the pic below of the board, nothing connected to the spades or the white wires,


Now.........

1) Run a single wire (the optional red) directly from the battery's positive post directly to the J3 (battery +) spade connector seen above.

2) Run a single wire (the optional black) directly from the battery's negative post directly to the J4 (ground/battery-) spade connector seen above.

Check Voltage.........

3) Connect the meter's negative probe - directly to battery negative post.

4) Using the meter's positive probe +, now probe/touch the J3 (battery +) spade connector seen above where the red wire directly attached to the J3 spade......12V?

I'm confused. It seems like you want to me to run wires from battery + and - to J3 and J4, then check for voltage on the ends of those wires. Assuming the wires are good, there will of course be voltage there.

Are you trying to verify the ground to battery? I will do this after work, just trying to keep up with what I'm doing so I can gain an understanding of all of this.

 

[gm280]

Just to let you know, I am watching now in the back ground. I am interested in seeing what becomes of this TM.

 

[sam am I]

Just to let you know, I am watching now in the back ground. I am interested in seeing what becomes of this TM.

I'm confused. It seems like you want to me to run wires from battery + and - to J3 and J4,

Yes, exactly.........We're making a very basic baseline to move up from....Apologies if it seems too simplistic, see below for explanation.

The board/PWM should (does) power up (relays click) with simply just these two wires hooked up as I requested (J3 to Batt+ and J4 to Batt-) and pinching the flex.

If the board remains dead with just this simple test, we have other issues hence, I need this step done just as prescribed plz so we know where were going next.

then check for voltage on the ends of those wires.

No, well yes BUT, only check the positive end of the wire at the J3 (for now), the meter's negative lead is to remain on the battery's negative post (see # 3 above in post #64)

Assuming the wires are good, there will of course be voltage there.

Correct BUT, the readings/feedback from the/your foil readings aren't making sense to me, perhaps something is getting lost in translation, wiring, etc, not sure BUT, we definitely need a very very basic setup to move up from to clear up a few things.

Hang in there, we'll beat this thing into submission just by shear persistence if we need too!!

I will do this after work, just trying to keep up with what I'm doing so I can gain an understanding of all of this.

Np and you're doing fine, it will make sense soon, no magic here.

 

[sam am I]

Rev 1.2

Correction to flex pot...........Vref from UC3842 is centered on carbon pad.

 

[gm280]

I hate to interrupt this trouble-shooting section, but "sam am I", since you have an exact model of it, if he were to send you the head unit assembly, minus the motor assembly itself, you could easily compare everything with yours. Probable easier then back and forth like you all are presently trying no here. And then you can connect everything up and mimic/mock up yours for testing and repairing whatever is the problem. Then ship it back and he just needs to wire in the motor wires and happy trolling again. Just an idea. :noidea:

If I would have had more then just a circuit board, I could have tried everything out as well. But I went merely on the premise that if there were any defective component(s), fixing/replacing them would solve the problem. But since there are other items that also needs to be working correctly, it has now taken on a totally new effort. JMHO

 

[jeepwm69]

Well, apparently Sam I Am was correct in the "let's start from point A again". I feel stupid.

I had the neg to J3, and pos to J4...... Wow.

So, I swapped those around. Of course now the bottom of the board shows 12V when probed with + probe and - probe on battery ground (like it's supposed to, right?)

Checked pins on 5 and 7 again and got .03 Volts regardless of position of switch.

I also pushed in on the disc with motor on and didn't get any clicking, and no motor movement, so I guess we are now at "he finally go the power leads hooked to the right place after only 5 pages"

Hopefully I didn't fry anything.

I'd be happy to mail this to either one of your for testing, or we can hash it out online where troubleshooting will be there for future generations. I've fixed a lot of stuff with google by finding old threads with the same issues.

 

[sam am I]

Jeep,

It's all good man! This is exactly how we ALL have learned......

I need a shower and coffee BUT, a good engineer has learned his/her lesson too here and in his/her lesson book, s/he knew his/her design would perhaps be subjected to just what happened, someone might reverse the power leads, D1 should have saved our cookies!!

But why no click? hmmmmmmmm, we'll soon find out.

 

[sam am I]

Probable easier then back and forth like you all are presently trying

I never take the easy path gm

Stay with me gm, no bailing!!!.............lol

bottom of the board shows 12V when probed with + probe and - probe on battery ground (like it's supposed to, right?)

Yes

Checked pins on 5 and 7 again and got .03 Volts regardless of position of switch.

With no click, this is what I would expect, this is a good thing!!

Hopefully I didn't fry anything.

No, D1 prevents current from flowing (one way valve for current if you will) if power is inadvertently reversed

I'd be happy to mail this to either one of your for testing

Not sending it to me sir! I'm hell bent on YOU fixing it

or we can hash it out online where troubleshooting will be there for future generations.

Agreed

 

[sam am I]

Next?

First and foremost...........Add a inline fuse in the battery's + wire!! Splice a fuse in........For now, a few amps is fine

Leaving the board hooked up in the "simple, back to basic's" setup (battery + wire to J3 and battery - wire to J4 AND nothing hooked to any of the white wires).

Leaving the meter's negative probe still on the battery's neg post...........and referring back to the pic of the board in post #64 and the schematic in post #69, locate pin #1 of the flex connector J1.

Using the meter's positive probe and moving over one pin to the right of pin #1, locate pin # 2

1) Measure pin #2 on J1. Voltage reading is? (Should be approx 5.8V.)

2) Leaving the probe on pin #2, press in/pinch the flex pot over the black carbon area. Voltage reading is? (Should change from the 5.8 measurement in step #1 above to somewhere between approx. 4V and approx. 1V dependent on where on the flex pot carbon area you press.)

 

[jeepwm69]

I'll try that after work.

Thank you again for taking the time to help me figure this out.

 

[sam am I]

Np Jeep,
Derivations..........again, no magic! I hope.........:ranger:

From post #74 step 1 above)

Given by,

At idle, the op amp U1's negative input (Vin-) or pin #2/3 flex = (Vcc - Vf d1)/2 = (12V - .5V)/2 = 5.75V

From post #74 step 2 above)

Vref (5V) of the UC3842/U2's pin #8 coming online (relays powered up) combined with a varying resistance as pressed on of the flex pot now sets U1 Vin- or pin #2/3 flex

Given by,

R-Flex = 1.3K = (R = 2.6K// F = 2.6K)

Vin- high = I Vref * R-flex + R2 = Vref/(R1+Flex+R2) * R-flex + R2 = 5/(470+1.3K+510) * 1.3K + 510 = 3.96V

Vin- low = I Vref * R2 = Vref/(R1+Flex+R2) * R2 = 5/(470+1.3K+510) * 510 = 1.11V

 

[jeepwm69]

Checked that. I have nothing going to any of the terminals on the desk (J1 flex)

 

[sam am I]

Checked that. I have nothing going to any of the terminals on the desk (J1 flex)

Just now with our new base line or back before?

If just now and with the board powered with our basic two wire setup still AND still with the meter's probe on the battery's neg post, find the diode D1 on the pic of the board (post #64) and probe both left and right leads of the diode.....

What are the voltages? One side/lead should be equal to the battery's voltage (see schematic in post #69) and the other side/lead should be equal to the battery's voltage minus 0.5'ish volts.


Correction from above.........Vin- high = I Vref * (R-flex + R2) = (Vref/(R1+Flex+R2)) *(R-flex + R2) = (5/(470+1.3K+510)) * (1.3K + 510) = 3.96V

 

[jeepwm69]

Just now (or yesterday after work)....

So check diode D1 and one lead should be 12.46 volts (current battery voltage) and the other should be approx. 4 volts (based on your correction)?

 

[sam am I]

Just now (or yesterday after work)....

k

D1 and one lead should be 12.46 volts (current battery voltage)

yes

and the other should be approx. 4 volts (based on your correction)?

No, that was for the op amp U1's negative input/Pin #2 flex.

Sorry if I confused the issue. Never mind this stuff, it was how to arrive at the expected/measured voltages we were looking for on the flex through all the resistors if the UC3842 powered up........We have issues and bigger fish to fry up stream looks like.

other side/lead should be equal to the battery's voltage minus 0.5'ish volts.

= "12.46V" - 0.5'ish V = 12V



Briefly.......A diode has two sides obviously, one side has a band designating the cathode (white usually if the diode's body is black which is in your case).

In this design and what you've measured on the non-banded side (anode) is 12.46V (the current battery voltage).

The other side (the white banded side/cathode) should be around 12V = ("12.46V" - 0.5'ish V = 12V) if the diode is good AND is forward conducting current...........(which it should be doing in our current setup and is perhaps why the flex voltages are not there)

Can you tell me what make and model number of meter your using? and/or if it has a "diode check" function?