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Check Engine Light - Can’t read with Tool

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Wereknight View Drop Down
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    Posted: 30 November 2013 at 1:53pm
Hi There,

I'm brand new to the forum and hoping someone has some
ideas for me on what I can to to fix my 85 2m4 2.5L 4Cyl
Fiero.

What would cause the check engine light to stay on and
not be able to clear?

Car starts just fine, but the check engine light will not
go away, flash the codes, or be read by Auto-Zone's
reader.

I've tried the following:
    1. took car to 2 different parts stores and a
    mechanic, none of them could get the reader to read the
    codes

    2. Tried using the manual code retrieval method of
    grounding the pins ALDL port next to the cigar lighter in
    the center console and switching the key to "on" - no
    flashing of codes, just stayed on constantly

    3. Tried clearing the code memory by:
      1) removing ECM fuse for 20 seconds (Chilton
      Manual recommended 10 seconds),
      2) removing all fuses and leaving them out for 2 min,
      3) disconnecting positive battery cable for 5 min,
      4) disconnecting both positive and negative battery
      cables for 30 min, turning the key to start while it was
      disconnected (to clear any residual system power).

After each of the attempts to clear the ECM memory I
started the car and the check engine light never blinked
or anything, just always stays lit.

Could this be caused by a bad ECM? is there a trick or
something I'm missing that might otherwise work? Could it
be just a bad ALDL?

Thanks in advance for any help you can provide.
    
~Wereknight
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Dr.Fiero View Drop Down
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Post Options Post Options   Quote Dr.Fiero Quote  Post ReplyReply Direct Link To This Post Posted: 30 November 2013 at 2:02pm
Could be a bad ECM.

Remove the console (back half). Disconnect the ECM. Turn the key on.
If the light goes out, bad ECM. If it stays on still, short to ground in the
harness.
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Wereknight View Drop Down
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Post Options Post Options   Quote Wereknight Quote  Post ReplyReply Direct Link To This Post Posted: 30 November 2013 at 2:31pm
Awesome!

I'll try that and report back.

Thanks for your help.
~Wereknight
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