MEP-803A No power at the panel

[chilbun28]

Hi, I just bought a 803A for my parents as mine has proven to be the ticket for my needs. The one i just bought is a 2007 model, just got it home and did a filter and fluid fill, put in hot batteries and absolutely no power at the panel, no response from the fuel pumps, no panel lights, no clicks, nothing. The little circuit breaker behind the panel doesn't appear to be tripped, the fuse looks good, and the emergency stop switch is pulled out. I tried the dead crank switch and the motor turns over so i put the switch back to normal. All wiring behind the panel looks factory with nothing out of place. I assume i need to start testing switches although i haven't ever dove into using a multi-meter much. Is there anything simple i'm overlooking or a good go-to place to start finding where i have power and where I don't?

 

[Light in the Dark]

Do you have the -24 manual for this machine? Its available in the TM forum. PDF Page 55 Starts the troubleshooting steps for "1. ENGINE FAILS TO CRANK.".

 

[Ray70]

Check the CR1 diode in the left rear corner of the control cube. I think it's the 2nd one up from the bottom??
If that diode is blown you will have no power at the panel.
I also assume by little circuit breaker you mean the round black DC circuit breaker button to the left of that AC select switch was OK?

 

[chilbun28]

Check the CR1 diode in the left rear corner of the control cube. I think it's the 2nd one up from the bottom??

If that diode is blown you will have no power at the panel.

I also assume by little circuit breaker you mean the round black DC circuit breaker button to the left of that AC select switch was OK?

10/4, I will check it in the morning. Yea. The DC circuit breaker is the one that I looked at and made sure the button was pushed in.

 

[chilbun28]

Reading a different thread with the same issue. I found MT-4 shunt. I have 24 volts on both sides of it. I went to CB-1 and I'm not getting a reading on either side of it. I'm assuming the circuit breaker is the, or part of the problem. Forgive ignorance here. But I would have assumed I would have had voltage on one side of the cb but not the other if the cb was bad......

 

[kloppk]

Put the Dead Crank switch in NORMAL, Emergency Off pulled out, CB1 pushed in, S1 in Prime/Run.
Now check for about 24 volts at the following points in this order.
Left side of MT4
Right side of MT4
Right side of CR1
Left side of CR1
Both used terminals on Emergency Off Switch
Both terminals of CB1

Post up the DC voltages at each of those points and it will narrow down where the issue is.

 

[chilbun28]

Dead crank in normal, e-switch pulled out, cb-1 pushed in, S1 in prime/run and using the ground stud on the lower right inside of the panel for my ground probe.

MT4 reads: 25.38 on both sides

CR-1 reads: 15.2 on the right side and 120 with the value slowly falling to 108 in about 10 seconds, this really doesn't make sense to me.

E-switch reads: zero on both terminals

CB-1 reads: zero on both terminals.

MT4 is not labeled, but I'm quite sure I identified it. I will attach a photo.

 

[kloppk]

Yes, that's MT4.
I suspect you may not have been on CR1 for your measurements of it. The stenciling by it can be misleading. CR1-2 is connected to MT4 by wire 112A.
Recheck the readings and be sure you are on CR1.

The 120 and falling reading was likely millivolts not volts.

 

[chilbun28]

Yes, you were correct, sorry. My reading on cr1 which is fed by wire 112a16 is 25.12 volts on the left side and 25.42 volts on the right side.

 

[kloppk]

Ok, good.
Looks like power is not getting to the Emergency off switch.
Power us going from Car1 to the Dead Crank Switch since you can dead crank the set. Issue is power is not getting from the dead crank switch S10 to the Emergency off switch S17.
The path for that is:
S10-3----wire 133A---P7-14- J7-14---wire 133B---S17-1

 

[loosegravel]

Ok, good.
Looks like power is not getting to the Emergency off switch.
Power us going from Car1 to the Dead Crank Switch since you can dead crank the set. Issue is power is not getting from the dead crank switch S10 to the Emergency off switch S17.
The path for that is:
S10-3----wire 133A---P7-14- J7-14---wire 133B---S17-1

My guess is P7/J7. I’ve been seeing corrosion issues there on a couple of different units.

 

[chilbun28]

I unplugged that plug and looked at it. It mostly looks clean although I will spray some contact cleaner on them later today. When I plug it back together and get the Grove lined up it does feel like it pushes in much at all. I don't think the plug is plugging in all the way but it could just be me.

 

[kloppk]

I see corrostion. Clean it up as best you can.
Plug the connector in and turn the locking collar on P7. That will draw P7 and J7 together fully.

 

[chilbun28]

If that still doesn't get it I assume I should be testing the output side of the dead crank switch wire that runs to the plug. ....

 

[kloppk]

Yes as listed in post #10

 

[Mullaney]

I unplugged that plug and looked at it. It mostly looks clean although I will spray some contact cleaner on them later today. When I plug it back together and get the Grove lined up it does feel like it pushes in much at all. I don't think the plug is plugging in all the way but it could just be me.

.
After you get that connector as clean as you can - note that corrosion that @kloppk mentioned - use a little Anti-Oxidation Paste to ward off future corrosion. While you are cleaning, use some electrical contact cleaner too.

 

[chilbun28]

I'm working nights tonight, I am getting contact cleaner and will try to find the oxidation paste. I will be back on it tomorrow. If the plug is my issue do I cut the plug out and hardwire the wires together with butt connectors? I appreciate yalls help!

 

[Mullaney]

I'm working nights tonight, I am getting contact cleaner and will try to find the oxidation paste. I will be back on it tomorrow. If the plug is my issue do I cut the plug out and hardwire the wires together with butt connectors? I appreciate yalls help!

.
Everybody has an opinion, but I would you think that you will be happier if you get that connector fixed. Butt connectors work, but a little testing with a meter before you hack up your wiring.

 

[chilbun28]

If my dead crank switch is not sending power out are and needs to be replaced is their a cross reference part number available for a like for like switch I can buy?

 

[loosegravel]

Since your dead crank switch is working, then the open circuit to your panel is elsewhere. Th