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Teeshot1939's avatar
Teeshot1939
Explorer
Jul 26, 2017

Is this good or bad or ?

Thinking of purchasing a 2009 Tiffin Allegro Bus 43QRP but am new to diesels and the current owner is unable to answer my questions. What is a VMM 1210? Are the red lights good, bad or ? Any info would be appreciated!
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    WHen you say "Are red lights good or bad" We are unable to answer that.

    We need to know what lights are red.

    But the General rule for indicator lights is RED=BAD That however does not always apply

    For example.. ON many diesels there will be a red light come on at first but goes away swiftly.. That is normal (IN fact 2 or 3 of em) it

    ON a gasoline engine OBD-1 (I used to have one of those) When you went to read the error code with the ignition on but engine not running you always got an 8-8-8 What did that mean.. It means the ignition is not on and the engine is not running (No signal from ignition pick up) so instead of being an error code it meant "you successfully jumpered the leads" to get the blink out.

    Oh, that too was a red (Check engine) light.
  • On Tiffin VMM red lights are GOOD. They just show what circuits are active. The system is almost foolproof. Tiffin used the system and hired the Engineer that designed the old out of business Western Alpine diesel motorhomes. He designed the electrical chassis systems for Western and Tiffin hired him to design the systems for Tiffins Powerglide chassis. The system has the capability for a authorized Engineer to connect a Laptop to change parameters of the operations of the Powerglide chassis. Or even diagnosis problems. Doug
  • Thanks for the replies. I read the manual but with terminology like..... "The VMM1210 has 8 digital inputs capable of reading either active high or active low type digital inputs. In addition, it has 4 inputs capable of reading analog voltages, frequency values or active low type digital inputs".... I am still lost to what this thing is actually supposed to do. Is it a fancy fusebox? Is it a set of switches?
  • Ivylog's avatar
    Ivylog
    Explorer III
    I probably would have posted this in the class a form. The multiplex system is one of the reasons I would not replace my DP with one much newer if I had to. When it works it's great but when it doesn't it can be hard to find the problem. You can download the following and start learning:
    https://www.parker.com/literature/Electronic%20Controls%20Division/Literature%20files/VMM1210_Instruction_book_HY33-5001-IB.pdf
    The red leds (12 in & 12 out) indicates what inputs there are and if that item is active...on.

    Before buying I would make sure everything works that it controls and if not I would not buy until the problems are fixed at the sellers expense.
  • First you should be more selective in your choice of a title for your topic !

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