Failure gauges dashboard FCCC Serial...

Ariel Guzman 71 posts since Nov 13, 2015
Failure gauges dashboard FCCC Serial No. L63820 Nov 4, 2020 1:41 PM
Hello everyone
The vehicle belonging to a family member does not have the dashboard clocks working. Example:
speedometer, oil pressure, engine temperature, etc. I have to travel to review it and I would like to take an
orientation and ideas that you can share with me.
Grateful
I attach images.
Cheers
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20201101_130253.jpg 4.3 MB

Jon Cecil 881 posts since Nov 25, 2014
Re: Failure gauges dashboard FCCC Serial No. LC63820 Nov 3, 2020 4:20 PM
That serial number isn't coming back to anything. Take a look at SS 2107 FCCC - MMDC Trouble Shooting /
Operation Manuals. This has some troubleshooting for the older systems.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 4, 2020 1:42 PM
Hi
I had made a mistake entering the serial number. I already edited.

Kyle Siebert 4,084 posts since Nov 14, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 2:12 AM
I think I have worked on a setup like this. All the gauges (clocks) were INOP. I unplugged all the gauges and
reconnected one to see if it worked. If it didn't I unplugged it and reconnected another and it just so happened
to work. Reconnected all gauges except the one and everything worked. The one gauge was dropping all
other gauges out.
But I believe I had another truck that didn't work on. Tech support said try test gauges or annocator. All
gauges ended up failing and we had to replace all $8,000 worth of gauges with nothing to test as to why they
failed.

Jon Cecil 881 posts since Nov 25, 2014

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Failure gauges dashboard FCCC Serial...

Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 2:41 AM
I had this happen but the customer said there was only 7 volts on a wire that he felt needed 12 volts. All
gauges were inop. Ended up replacing all gauges as well. The unfortunate thing I ran into on mine was some
gauges were obsolete and unavailable. I had a mixture of red and green backlighting. It looked like it was the
holidays in it.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 7:19 PM
What voltage should the cable have, 7 or 12 volt?
Greetings and thanks

Jon Cecil 881 posts since Nov 25, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 10:04 PM
It is suppose to be 7 volts. It should say it right on the wire that it is 7 volts. Do not put 12 volts to it.

Keith Krebs 128 posts since Nov 10, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 12:24 PM
This unit is old enough that it has a VDC instead of a MMDC which means it will be behind the rear axel, a lot
of times under the bed. When I have had this problem in the past it is usually the VDC. If you have a test one
take it with you. It can save a lot of time troubleshooting.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 7:12 PM
Do you have a reference image of the VDC ?.
I do not know him and I have never heard that device.
Greetings and thanks.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 7:14 PM
This is waiting for me expectantly!
I hope that with your advice you will find the fault.
Thank you

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Failure gauges dashboard FCCC Serial...

Keith Krebs 128 posts since Nov 10, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 7:19 PM
VDC IS IN PARTS PRO, BOM 353 AND THE VIEW IS KYS153910167. CALL THAT UP AND IT WILL SHOW
A PICTURE OF IT.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 8:47 PM
How good
Thanks for your help.
Cheers

Keith Krebs 128 posts since Nov 10, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 7:30 PM

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Failure gauges dashboard FCCC Serial...

If you have access to Service Bulletin 54-12 it will give you all the info. I am attaching a pic of the VDC and a
page from the SB showing the inputs

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Failure gauges dashboard FCCC Serial...

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Failure gauges dashboard FCCC Serial...

Hope This helps.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 5, 2020 8:46 PM
Oh nice.
Thanks for the info.
Grateful.
Cheers

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 24, 2020 1:58 PM
Hello everyone
I check the motorhome and find that it has been intervened by several technicians observing cut MC power
cables and 7 volt cable bridged to 12 volt. I tell the owner that this connection is wrong and I explain that I
have to correct it to make a diagnosis. I followed the TS of the procedure that you sent and got to the part of
renewing the VDC. I have doubts.
The MC does not turn on fully, nor control lamps and clocks. I check the MC and VDC power supplies being in
order. The VDC sends the trigger signal (Ground) to the MC and sends J1587 communication voltage as well.
I came to the conclusion that the MC is faulty.
The problem is now to get the replacement, but that is another matter.
Greetings and thanks to all.

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Failure gauges dashboard FCCC Serial...

Jon Cecil 881 posts since Nov 25, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 24, 2020 2:48 PM
Most likely all the gauges will need to be replaced. I ran into an issue when someone jumped it with 12 volts. I
do not remember changing the LCBU or the VDC when this occurred though.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 24, 2020 3:14 PM
oh what bad news I have to deliver!

Jon Cecil 881 posts since Nov 25, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 24, 2020 5:02 PM

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Failure gauges dashboard FCCC Serial...

Especially those gauges came in 2 different backlighting colors. Red or Green. The last time I had to order
them, some of the reds were obsolete and some of the green were obsolete. I had to replace with a mixture to
get it working. Looked like a Christmas tree.

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 24, 2020 5:48 PM
jajajaja XD

Michael Palumbo 1,496 posts since Nov 13, 2014
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 26, 2020 12:47 AM
Yes 12v will destroy a gauge.
test 6.

Reference the caution on page 38, just after TROUBLESHOOTING GAUGES

Edited Instructors Copy of System III and MMDC.pdf
https://www.dtnasolutions.com/docs/DOC-1032909

Ariel Guzman 71 posts since Nov 13, 2015
Re: Failure gauges dashboard FCCC Serial No. L63820 Nov 26, 2020 5:24 PM
Thank you.
regards

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