Freightliner instruments not working 1999 Winnebago Ultimate Freedom 38'

BobS · 08-07-2022, 10:26 AM

We bought a 1999 Winnebago Ultimate Freedom 38' last year. It had not been well maintained so I have been going through the issues one-by-one. The problem(s) I have remaining are related to the instruments. In short:
* speedometer/odometer do not work. Odometer did record about 2 miles in a 60 mile drive so there must be some connection.
* tach works when ambient temperature is below about 45. then slowly stops working as the vehicle warms up. in the same 60 mile drive, it worked for about the first 15 miles then slowly started falling until it read 0.
* fuel gauge shows full when tank is full. Shows empty when tank is 1/2 full. Bounces like crazy when driving down the road and hit a bump
* cruse control WORKS.
* instrument panel has been tested and showed no problem.
* installed a Scan Guage in the OBD port (6 pin). Tach and Speedometer readings are perfect. Fuel consumed even appears to be accurate.

So I am assuming that all of the sending units are most likely working properly, with the possible excepting of the fuel. That would lead me to a poor connection/bad ground somewhere between the sending device and the dash. What I think I need to know is where the sending unit is for these signals and a pinout for the big plug in the instrument panel that would tell me what pins the tach, speedo and fuel signals come in on. This is on a Freightliner chassis (1998) with a Cummins turbo 350. Can anyone please help me with getting this information? Any other helpful suggestions would be welcomed.

Thanks.

Oldchinahand · 08-10-2022, 09:52 PM

Just responded to a similar issue with a 2002. And we had it. Freightliner had a stealth recall on the twisted wire harness leading to the gages back in 2010, I believe. We were able to get them to honor the recall in 2019 and replace our harness (actually, WWWilliams did, but.....) Others bought a new harness and installed it themselves. The harness is small and (dare I say it) intuitive to self install.

Fair Winds and Following Seas

BobS · 02-18-2023, 07:38 AM

Where can I get the information on the harness? I just finished talking to the shop in Minneapolis that checked my cluster. The cluster is good so the issue must be the wiring going to the cluster.

FYI if you need help with instrument clusters, try D&D Speedometers in Minneapolis. Super helpful folks.

tim myers · 02-18-2023, 11:30 AM

Call 1-800-FLT-HELP, have your VIN available that is where I ordered my new twisted pair wires

Ray,IN · 02-18-2023, 03:34 PM

FWIW, over 80% or all 12V problems are the result of a poor/missing ground.

BobS · 02-20-2023, 08:07 AM

that number does not work. It takes me to a recording that says to go to a website.

BobS · 02-20-2023, 08:30 AM

OK 1-800-FLT-HELP is 1-800-358-4357. That doesn't work.

1-800-FTL-HELP is 1-800-385-4357. That does work.

I contacted them and they said they had no information on any recall and there was no wiring harness except the main, all inclusive harness (50 or so wire) available.

They are sending me schematics so I can attempt to run 2 twisted pair signal wires from the transmission area to the instrument cluster.

FYI. I know that the instrument cluster is good (had it tested) and the sensors are good (ScanGauge D correctly reports ALL readings including RPM and MPH). That leaves the signal wires as the only component left.

tim myers · 02-21-2023, 01:12 PM

I apologize for the phone number error. I had watched a YT video and the repair man had shown an issue with the gauges on the Freightliner. When I contacted Freightliner the guy I spoke with did know about the issue. FL never made it a recall as that would infer they were giving the parts away. I had to purchase a wiring kit for I think $127.

My issue was that the front air tank gauge would show a zero pound air pressure at engine startup along with the accompanying alarms. The gauge would then jump to 125# then drop back to zero #. In my opinion the reading and alarm was a false indication.

My original twisted pair wires were white in color and the replacements were black in color. I have heard that the wires is a bit heavier to handle voltage drop. Replacing the wires took care of my issue.

That said, Freightliner had an upgrade / changeover to a different system of distributing the signals to the gauges sometime around 2002 - 2004, and my coach is a 2007, so the wires may have nothing to do with your issue.

I am sorry if I sent you on a wild goose chase.

BobS · 02-22-2023, 12:34 PM

No problem at all. My unit is a 1998 chassis and the signals for the tach and speedometer are sent via twisted pairs from the ECU. What your information gave me was a Freightliner number. They sent me the wiring diagrams so now I am going to see if my local RV repair shop will run some new twisted pair signal wires for me. They said they couldn't before because they didn't have the wiring diagram. So thanks to your Freightliner contact, I may be a step closer to getting my tach and speedo working.

thanks for your help.

BobS · 02-22-2023, 12:43 PM

I should have mentioned, since mine is a pusher, the signals run from the engine/transmission area in the rear to the dashboard. That's a long run for analog signals. I guess that's why the signal is AC not DC.

tmartin · 02-21-2024, 07:01 AM

Did you get the problem fixed? I have a 1999 Ultimate Freedom with the EXACT symptoms. Tach, speedo, air pressure and fuel guage blow 1/2 tank. if you have anything that could help me fix this.

Thanks in advance!