Where to get wiring diagram for my Western Star?

Discussion in 'Trucks [ Eighteen Wheelers ]' started by Floyd, Oct 13, 2011.

  1. Floyd

    Floyd Light Load Member

    Messages:
    163
    Thanks Received:
    22
    Joined:
    Jun 1, 2010
    Location:
    Central Maine
    I'm having electrical issues with my '95 W. Star. The truck had been sitting for a few months. I was taking it over to the shop to service it before using it again and the engine quit on me. I could hear the electric/air fan solenoid clicking on and off and the tach was going crazy. It wouldn't start at first(just turned over) then it fired and ran. This happened several times. Everything else has power but it seems that the ECM is losing power intermittantly for some reason.
    I used my cruise switch to pull a 34 code which was something to do with RPM signal.
    I'm hoping it's a bad connection somewhere but i'm starting to have my doubts.
    If had any thoughts or knew where to get a wiring diagram that would be great.
    Thank you.
     
  2. Pablo-UA

    Pablo-UA Road Train Member

    Messages:
    7,140
    Thanks Received:
    1,314
    Joined:
    Oct 11, 2010
    Location:
    Borispol, Ukraine
    I sugest it shares a lot with Freightliner Classic. Anyway, simple wiring
     
  3. Heavyd

    Heavyd Road Train Member

    Messages:
    3,896
    Thanks Received:
    1,597
    Joined:
    Feb 4, 2009
    Most engine ECMs get their power from a dedicated wire harness straight from the batteries. Normally there are a couple of connectors and a fuse in there somewhere. These are perfect locations for corrosion to set in. Try checking for this harness and follow it the best you can and check all the connections.
     
    SHC Thanks this.
  4. fortycalglock

    fortycalglock Road Train Member

    Messages:
    5,078
    Thanks Received:
    4,258
    Joined:
    Jun 25, 2011
    Location:
    Tourist Town, FL
    On my 2000 WS, the ECM power wire goes to the firewall above the engine, through a fuse, terminates and then goes to the battery box. I'd check this first. Also make sure your battery terminals are tight. I've had a ring terminal break off and kill power to the truck while riding down the road before.
     
    SHC Thanks this.
  5. billm89

    billm89 Bobtail Member

    Messages:
    26
    Thanks Received:
    12
    Joined:
    Jul 20, 2011
    Location:
    Mass.
    If you have access to a computer, go to www.accessfreightliner.com.Click on the register for access link and there is a form to fill out to be able to log on for vehicle specific parts and wiring diagrams. It's faster if you bring the form to your local dealer, and they can get you hooked up. I have used this site quite a bit both for parts lookup as well as wiring info and it's excellent. You only have to register once, and they give you a password that you use anytime you need to get on. Good luck!
     
  6. Starline

    Starline Medium Load Member

    Messages:
    356
    Thanks Received:
    233
    Joined:
    Jun 1, 2011
    Location:
    Middle Tn
    1st check and clean all your grounds. Most all electrical issues are traced to bad grounds. I'm talking the grounds at the starter and where the cable goes to the frame. (be careful not to break the solenoid on the starter).
     
  7. SHC

    SHC Spoiled Rotten Brat O/O

    Messages:
    8,587
    Thanks Received:
    6,870
    Joined:
    Feb 26, 2011
    Location:
    Westville, IN
    I just went thru this 2 days ago with my 04 Lowmax.... the ECM/DASH gets it's power supplied thru a dedicated wire harness that connects at the battery terminals. Mine had corroded connectors but I could not tell they were until I removed them and they fell apart. Take off the battery box covers and check. If you have dual boxes like I do, they will be on the drivers side box.

    Hope that helps
     
    04 LowMax Thanks this.
  8. Floyd

    Floyd Light Load Member

    Messages:
    163
    Thanks Received:
    22
    Joined:
    Jun 1, 2010
    Location:
    Central Maine
    Just an update. After a couple days in the shop chasing wires and checking connections, wires, grounds etc. the truck ran pretty well yesterday.
    I found that my switched power to the ECM seemed fine, but I ran a bypass wire from a known good power source just to be sure. Truck sat and ran for a while so I thought I had it............and then it shut off like it had been.
    Basically I was at the point where it had to be the ECM, but since the truck sat for a couple of months I was still hoping on a moisture issue so I hooked her up yesterday morning anyway and went to work(just locally).
    It shut down maybe 3/4 times and coughed a couple others before I could haul my first load, I thought great!
    But after the first few fits it ran like a top the rest of the day! Hopefully my theory on moisture was correct but only time will tell.
     
    SHC Thanks this.
  9. Harleychikka

    Harleychikka Bobtail Member

    Messages:
    1
    Thanks Received:
    0
    Joined:
    Mar 22, 2015
    Location:
    MI
    Problem with that is they take 3 weeks to give you access, and that's if they approve you... i need an answer now...http://www.thetruckersreport.com/truckingindustryforum/images/smilies/roundies/biggrin_25521.gif
     
  10. SpeedRacer

    SpeedRacer Light Load Member

    Messages:
    142
    Thanks Received:
    11
    Joined:
    Dec 4, 2007
    Location:
    Tifton, Ga
    I 2nd the Access Freightliner, I use it a lot. It gives you access to all the same schematic and install diagrams the shop can see. If you need the schematics quickly though, a friendly dealer can look them up and print them for you. That's how I started getting them. Some may be less willing than others, doing business with them regularly helps.
     
Draft saved Draft deleted