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RE: Source to test a single Circuit Board
Look at the bottom picture. The trace that goes along the bottom. You should have the regulated voltage along this trace.
I got no voltage reading along that trace. As I recall when I put my positive lead on the trace I got a -0.00 reading.
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deandec
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12/18/09 06:55pm |
Technology Corner
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RE: Source to test a single Circuit Board
OP Here again:
The above measurements were replicated today.
I also did the diode test of the Same silver tower transistor:
(Black lead to Red Lead)
Pin 1 to 3 0.85
Pin 3 to 1 0.50
Pin 2 to 1 0.65
Pin 1 to 2 0.00
Pin 3 to 2 0.56
Pin 2 to 3 0.61
I traced the output of the L7812 regulator 11.3V to SW1 wire. This passes through the center leg (pin2) of the silver transister. The pin at the transistor measures 6.86V.
SW2 wire sends 3.6V to the board when switch is pressed on. Also the NEC relay clicks and 255 Wire sends 3.6V to the Bosch Relay (off board).
The Grey/Green Capacitor in the upper left of the board has 7.3V in one side but 0.00V on the other side. The momentary switch has no effect on this component.
I have exceeded my techincal knowledge with this search so if anyone can offer a next step, I will greatly appreciate the reply.
Thanks to All
Dean
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deandec
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12/18/09 04:32pm |
Technology Corner
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RE: Maintenance Overkill?
...but there's really nothing that I know of that spells it out.
If you are fortunate to have your owner's manuals, the maintenance schedules might be there. They are in my old rig.
Engine Manual
Chassis Manual
Coach Manual
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deandec
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12/17/09 06:10pm |
Class A Motorhomes
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RE: Source to test a single Circuit Board
With the 12V applied but no switch action:
Pin 1 -0.00
Pin 2 6.86V
Pin 3 0.66V
With the Momentary Switch to the Board pressed:
Pin 1 -0.00
Pin 2 0.00
Pin 3 4.04
I will do that measurement again, but I think it will replicate the results from the previous measurement above. The output voltage does not get to Pin 2 of the silver transistor. My test today mirrored the first readings of Pin 1 and Pin 3.
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deandec
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12/16/09 05:28pm |
Technology Corner
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RE: Source to test a single Circuit Board
Looking at the picture with the fastening nut of the LM7812 up
Wire 164 from the fuse box to the Board 13.74 V (GenSet Was Running)
Left Leg 13.74 Volts
Middle 0.94 Ohms
Right Leg 11.83 Volts
Silver Transistor:
Pin 1 -0.6 DCV
Pin 3 0.65 DCV
I guess this says something between the Regulator and the Transistor is not working. The candidates are the red rectangular relay or the blue capacitor.
I will look for replacements.
OOOOps....I still did not do Myron's test of the transistor recommended a few days ago. Tomorrow.......
Dean
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deandec
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12/16/09 05:05pm |
Technology Corner
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RE: Maintenance Overkill?
I feel they build a safety factor into there requirements so the ones that don't follow it will have some lee way.
I hope so...My Gillig maintenance manual says to repack the Front Wheel Bearings every 12 mths or 12,000 miles. What a waste!!
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deandec
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12/16/09 10:57am |
Class A Motorhomes
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RE: Source to test a single Circuit Board
Top of Board Backlit
http://i32.photobucket.com/albums/d23/deandec/FreshWaterFillCircuitBoarddec011.jpg
Bottom of Board Backlit
http://i32.photobucket.com/albums/d23/deandec/12-15-09BacklitFWCBSmall.jpg
Top of Water Fill Circuit board
http://i32.photobucket.com/albums/d23/deandec/FreshWaterFillCircuitBoard011Small.jpg
Q. Pin 1 of silver Transistor, does it connect to output of Regulator?
A. It connects to the bolt that holds the regulator on the board.
Q. Is the Base, (middle pin) connected to S2?
A No, that pin is connected to a resistor which is connected to S1.
A. Pin 3 (Emitter) is connected to S2.
Q. ID small red resistor
A. It was very difficult to get some of the info and I have excellent close up vision. So here is my interpretation.....
MR3462 12 USA NEC 0.6A 110vdc, 2A 30VDC, 1A 125VDC, B9427
Q. What happens if wire 378 (tank full) is disconnected from board.
A. No noticeable affect to switch response.
I think I have listed all the open questions. I repeated the photos just to hopefully save my valuable guides some time. :)
Dean
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deandec
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12/15/09 04:45pm |
Technology Corner
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RE: Source to test a single Circuit Board
The only question above that I can answer with certainty, is that the volatage measurements were taken with the meter negative lead connected to a off-board grnd circuit to which the grnd wire from the board is connected.
I will collect additional answers later today.
Dean
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deandec
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12/15/09 12:29pm |
Technology Corner
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RE: The generator has 2,500 hours
What generator do you have?
What symptoms other than non-start do you have? Is the battery dead? Does it crank? Does it start then quit?
Is there plenty of fuel for the generator (diesel or LP?)
Do you have a pre-heat feature on the genny that you must use prior to trying to start it?
Is there adequate oil in the generator?
All the above could affect non-start condition.
Usually, the generator is started by the house battery, but some rigs use a dedicated battery.
2,500 hours is a lot of use but the unit should have 3x that left IMHO.
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deandec
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12/14/09 06:05pm |
Class A Motorhomes
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RE: Source to test a single Circuit Board
OP Here:
Also today, I measured the voltage to the board from the 378 wire. It was 8.66V.
I disconnected the wire (actually a leg of a resister joined with a junction of this wire) from the tank level indicator connection. It still had 8.66V at the circuit board.
Then I ran out of time. So I still have yet to actually cut the 378 wire from the board for a test. But, I first want to find out where that wire comes from in the 4 other ciruit boards in the console.
Dean
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deandec
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12/14/09 05:57pm |
Technology Corner
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RE: Source to test a single Circuit Board
OP Here Again:
Today I measured the voltage at the 2N 2907 Transistor legs. (I guess this is the same as a PNP PN2907 transistor which I can buy at Radio Shack?) (This is the silver water tower type component in the board picture.)
Pin 1 is the leg closest to the left side of the board in the picture.
Pin 2 is the middle leg soldered to a resistor
Pin 3 is the leg closest to the NEC Relay.
With the 12V applied but no switch action:
Pin 1 -0.00
Pin 2 6.86V
Pin 3 0.66V
With the Momentary Switch to the Board pressed:
Pin 1 -0.00
Pin 2 0.00
Pin 3 4.04
The above means nothing to me, but maybe someone can translate and diagnose the condition of this transistor from the above into?
Dean
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deandec
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12/14/09 05:50pm |
Technology Corner
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RE: Wiper Arm Washer Assembly
These folks might have what you need.
Amequipment
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deandec
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12/14/09 11:25am |
Beginning RVing
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RE: Repack wheel bearings on MH?
Or could I wait till fall before storage?
If all you want is an "on topic reply" the only good answer would be "Yes".
No other answer would be "on topic". You can do what ever you elect to do, its your rig.....??
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deandec
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12/13/09 05:37pm |
Tech Issues
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RE: When did Class A diesels first appear.
They can only get about 1/4 of what the owner paid for the unit new, so they just hang on to the older one.
I would really like to sell mine for 1/4 of new, but doubt that is possible..... :)
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deandec
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12/13/09 11:56am |
Class A Motorhomes
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RE: Do they make caulk or tape that I can apply in rain?
If you know where the hole is, use plumbers putty for a temporary fix. It may not hold driving down the road however.
I use the stuff to hold 20 gallons of water in a concrete water fountain, so it works.
I tried the duct tape routine, but that stuff would not stick to fiberglass...
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deandec
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12/12/09 02:49pm |
Tech Issues
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RE: Repack wheel bearings on MH?
Well, my rig is 15 yrs old and has 73,000 miles. It weighs 31,000 lbs and moves every month or more often. The bearings are greased, not oiled.
I have owned it for 8 yrs and 47,000 miles. I am going to have the front wheel bearings repacked and inspected this month or next. That may be the first time ever on this Gillig Chassis. The Gillig manual recommends service every year.
The rear wheel bearings are lubed by the differential lube and I see no leaks and have no noises, so I am ignoring those in the next service.
So, you can follow my example or be more cautious. :)
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deandec
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12/12/09 02:33pm |
Tech Issues
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RE: Suburban Furnace Outside Air Wheel
Excellent !!!!!
The wheel noise is gone.....:B
i had same problem took out motor found piece of rubber hose 3 inchs longer than the shaft on motor filled hose with grease and got bolt that slid tight into hose held hose down over shaft and pushed 4 or 5 times on both ends of motor
I would guess that the bearings on that side are dry, so either try to lube the motor, or replace it.
Just put some oil on the shaft next to the motor.
So, I only had the Combustion Air Wheel off the motor stem and that seemed to be the side that was howling. I used plastic tubing just as Bird 1959 said. I found a bolt that filled the hose end, bearing lube for my boat trailer, then slid the tube over the motor shaft filled the tube, pushed the bolt in, and bent the tube forcing the grease down the shaft.
Voila.....it runs like new. Time will tell of course, but I am very pleased right now.
I am not very creative, but I try to take instruction well.
THANK YOU, Chris Bryant, Bird1959, and Dusty for educating me and solving my problem.
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deandec
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12/12/09 01:46pm |
Tech Issues
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RE: Source to test a single Circuit Board
Thanks to all for the feedback. I am away from the rig until Monday.
1. I did replaced the big (size) NEC relay with the same part number.
2. I will disconnect wire 378 to see if it has an effect.
3. I will test that silver transistor and report back.
The interior LED still does not light up with or without the switch. I did replace the LED with a new one, but.....I forgot to observe the direction of the voltage flow of the old one. So, I installed it facing the same direction as the LED that does light up. 50-50 chance of being correct.
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deandec
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12/12/09 12:42pm |
Technology Corner
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RE: Suburban Furnace Outside Air Wheel
Ok, I will try the lube the motor thing since some have had success, it is free, and the parts store is closed.
BTW, on my parts list Item 350110 is "Wheel, Combustion Air" so I created the term Air Wheel :)
Dean
OP
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deandec
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12/12/09 12:34pm |
Tech Issues
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RE: General Question about My Garmin
At one time, my Steet Pilot 2620 displayed some high level maps but not the normal level of detail.
I later determined that I had inadvertantly told it not to load the most recent map detail stored in memory. How, I do not know.
So read through your setup instructions and review each step on your unit, perhaps you too have done something inadvertant to the setup.
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deandec
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12/12/09 12:10pm |
Class A Motorhomes
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