Problem with computer ..unable to receive codes

CADILLAC STS
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I have a 1997 STS with 123,000 miles on a Northstar engine. Car operates and runs fine. Problem is it cannot pass NYS inspection. When hooked up to inspection computer it gets no readings or codes. Even tried driving 120 miles without shutting off engine and hooking it up to computer with same results. What is happening ?
Can I get a used computer and have it programed for this vechile ? How do you check onboard computer ?
HELP !
Sep 28, 2007 at 8:57 PM
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MERLIN2021
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Pin # Description 4 Ground 2 serial data signal class 2 5 Ground 16 Power check for power at pin 16!


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Her's a bit of testing ingo..


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You should be able to go to a good part store and by a remanufactered one. Try unplugging and replugging the connector first! Remove negative Battery cable first!
Sep 29, 2007 at 7:00 AM
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BUZZSAW
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[quote:bb341d1efa="icemate"]I have a 1997 STS with 123,000 miles on a Northstar engine. Car operates and runs fine. Problem is it cannot pass NYS inspection. When hooked up to inspection computer it gets no readings or codes. Even tried driving 120 miles without shutting off engine and hooking it up to computer with same results. What is happening ?
Can I get a used computer and have it programed for this vechile ? How do you check onboard computer ?
HELP ![/quote:bb341d1efa]

you can go through the heater controls and see if the pcm will communicate, press off and warmer simotanisly, it will run through its codes
Oct 1, 2007 at 4:24 AM
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SERVICE WRITER
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I have seen a fair amount of communication failures from a blown fuse.
Oct 10, 2007 at 8:22 PM
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