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  1. #1

    Default Code Reader Issue

    Hey out there. My 97 Chevy Express 2500 'service engine soon' light appeared yesterday at start up in the morning. When I went to O'Reilly's to read the code it said "NOT CONNECTED". So we tried another reader and had the same result. Three weeks ago I changed plugs, wires, cap and rotor. Other than that no other changes recently. I notice no difference in how the engine is running, and it definitely runs better after the recent tune up I did. Also, I had just filled up the tank the night before this happened. So my question is how do I go about finding out what has caused the light to come on? Is there a chance the reader and the computer are not "connected" some how? Any help is appreciated as I am towing my son's car from Tulsa to Florida for school in 3 days!!
    Last edited by spaceball04; 01-22-2009 at 06:04 AM.

  2. #2


    Check the fuses. The fuse for the diagnostic connector is usually the same as the cigarette lighter.
    '98 K1500 Suburban LS 5.7 L 4L60E NV246 ARB
    '92 Ford Explorer XLT 4x4 4.0 L A4LD BW13-54 Trac-loc rear
    "My toys were the greasy cogs and springs and pistons that lay around all over the place, and these, I can promise you, were far more fun to play with than most of the plastic rubbish children are given nowadays." Danny in Roald Dahl's Danny The Champion of the World

  3. #3

    Default Thanks Mr Shorty

    Well I checked and the cigarette lighter fuse was blown. I changed it, headed off to the parts store and still no reading of the code. I went to the dealer as I was getting pretty desperate by this time. Still no connection. I went home and disconnected the battery and re-attached it. Bingo! No light and then hooked up a reader and it was connected showing no problems. I figure that the fuse was blown but with the connector and the computer not connected no way for it to reset? Made the trip to Florida and back. So thanks again, I now know that trick.

  4. #4
    Master Mechanic
    Join Date
    Oct 2008
    Brandon, FLA
    Blog Entries


    Good man, these and some of the other models for this year were notorious for this with the Cig Lighter connection to the Diagnostic connection, dumb a.. idea eh!!!!!!


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