OBD II will not link, any suggestions?

Discussion in 'General Chevy & GM Tech Questions' started by mocosho, Sep 22, 2008.

  1. mocosho

    mocosho New Member

    I recently acquired a 1997 LT Suburban, 5.7 L engine. After replacing the fuel filter, the Service Engine Soon lamp came on steady. I have a scan tool, but when I connect to the port, the screen remains blank and does not link (key is on, engine is off). I am familiar with using this tool, but I have not run into this problem of not communicating with the ecm. Any help would be appreciated. (BTW, I don't know if this is relevant, but the auxilary power oulets next to the cigar lighter have no power and yet all the fuses in both fuse boxes are good. Cigar lighter does have power. I can't explain that either.)
  2. werty

    werty Rockstar 100 Posts

    my brothers 99 3/4 ton gmc sle has the same problem :neutral:im going to be watching this one
    same here plug it in nothing...put it on another truck and itll read fine ......:neutral:
  3. MrShorty

    MrShorty Epic Member 5+ Years 1000 Posts

    The data link connector has a power supply, and the usual reason for the scantool not to work like that is because the connector has no power. I believe it's the same fuse as the cigarette lighter, but not certain.

    For the OP, if you are certain all of the fuses are good, then it's time to find a wiring diagram and see if you have power to the diagnostic connector, and, if not, trace the wires to find out why.

    For werty, 1st check the fuses to see if they are ll good.
  4. Crawdaddy

    Crawdaddy All hail the Mad King!! Staff Member 5+ Years 1000 Posts Platinum Contributor

    IIRC, the power wire on the OBDII connector for late 90s, early 00s is orange. My uncle's dually that went through Katrina had a similar issue. The terminal for the power was corroded away. I pulled the pin from a junkyard OBDII connector, dropped it in its place in the connector on the truck, spliced it in and off I went.

    EDIT: checked the diagrams, and it is an orange line in the pin 16 spot. it's being fed off of aux power fuse #7 (25 amp it's listed as). Hope this helps.
    Last edited: Sep 22, 2008
  5. mocosho

    mocosho New Member

    Thanks Crawdaddy and MrShorty, I rechecked my fuses and #7 was blown. Replaced fuse and scan tool linked up and my aux power outlets also powered up. As a newbi to the forum, I much appreciate the support from all of you!

Share This Page

Newest Gallery Photos