Looking for a Freightliner front air gauge

[Skip426]

Originally Posted by johntaves

That's a bluefire dashboard. Bluefire has an adapter that plugs into the 6 or 9 pin diag port (J1708/J1939) that probably comes straight from the engine and tranny. That data bus does not have air and fuel level, which are added by Freightliner to a different data bus that feeds the dash.

I am waiting for bluefire to report whether their adapter will plug into the dash bus that has the air and fuel, and hopefully that bus will still have the additional info that is on the J1708 bus.

John: I've had no luck tracking down the member who shared the photo with me but seeing that the picture was taken while on the road and showing air gauge readings, cruise status and fuel (which is added at the message center) either the Bluefire plugs in after the message center to pick up fuel reading or perhaps has multiple inputs from the message center and the diagnostic buss.
A second thought, I always have them, the data buss that feeds the message center, must also carry diagnostic data in order for the wait to start and check engine lights on the message center to operate.
I'll go over my wiring schematics to see if that's a possibility.

BTW, what year is your chassis?

[johntaves]

Originally Posted by Skip426

that feeds the message center, must also carry diagnostic data in order for the wait to start and check engine lights on the message center to operate.
I'll go over my wiring schematics to see if that's a possibility.

BTW, what year is your chassis?

Freightliner 04. It's got a Cat 3216. It has just the 6 pin.

I am concluding there should be no problem plugging the adapter into the message bus and/or the gauge bus. If the message bus passes along the same data, then the gauge bus will have the fuel level. As far as I can tell the buses are all the same RS-485, so I figure I can risk the cost of the bluefire.

However, I am hoping that bluefire will agree that it is OK.

My only concern is that the VDC makes sure that the message center is alive before it is happy to let me drive. RS-485 allows for multiple masters, so this is a possibility. I will give that a try in a day or so. I should be able to see any negative reaction from the VDC on the bluefire. There was no negative reaction when I tried to drive without the gauges plugged in.

[Skip426]

Freightliner's dash gauge package switch from the VDC system to the MMDC has been a topic of much debate, as to the exact introduction.

Do you have this module on your dash ?
The presence of this module would confirm your system as a MMDC and not the VDC system, that I thought was phased out in late 03 chassis production.
Yellow box in photo.

[johntaves]

Originally Posted by Skip426

Freightliner's dash gauge package switch from the VDC system to the MMDC has been a topic of much debate, as to the exact introduction.

Do you have this module on your dash ?
The presence of this module would confirm your system as a MMDC and not the VDC system, that I thought was phased out in late 03 chassis production.
Yellow box in photo.

I do not have that module.

http://ww2.justanswer.com/uploads/go...44_sbu5412.pdf
This matches what I have, but this description at the top does not "This information applies to 1999, 2000, 2001, and 2002 (through June 9, 2002) model-year vehicles."

[Skip426]

Originally Posted by johntaves

I do not have that module.

http://ww2.justanswer.com/uploads/go...44_sbu5412.pdf
This matches what I have, but this description at the top does not "This information applies to 1999, 2000, 2001, and 2002 (through June 9, 2002) model-year vehicles."

The pages of the bulletin also state " last up dated June 2004" at the bottom of the pages .
Why Freightliner chose not to redo the heading with EXACT dates for the use of the VDC gauge system is any body's guess.
Through many posts I've managed to figure out the start date of the system as Jan. 04,1999 , right after the Christmas assembly line shut down, as chassis produced in Dec.1998 still have analog gauges.
The dash module, I indicated in the MMDC system has DTC read/clear capabilities so is fully on the buss.

[johntaves]

Originally Posted by Journey32

The front air pressure gauge needle....Thanks, Gene in Idaho.

Did you find a replacement gauge? I am replacing all my gauges with a computer monitor, so I don't need my front air pressure gauge. Do you still need it?

I am not sure if I followed your problem and the responses from the others properly, so I apologize if I am confused. I don't buy the argument that the VDC or ground is at fault. I suspect you are saying that the gauge is buzzing and not the dashboard buzzer (for low air and other). If the VDC has a poor ground all the gauges and the row of idiot lights will be suffering. The gauges are receiving a digital packet and if the packet check sum does not add up properly, it should ignore the data. Certainly they could have made a poor implementation that ignores the check sum, but it makes no sense to me that only one gauge suffers from crap data, except to conclude the gauge is bad.

[Journey32]

I did find a gauge in the UK and during the shipment time skip246 explained how the gauges work so I pretty much knew I had wasted my $90. I did give it a try when I received it but it did exactly what the old gauge did. When it warms up here I'll be pulling off the VDC and doing the soldering thing. I do appreciate your reply and offer. I would like to know how your project turns out and if you like it. Thanks again, Gene