DTC Codes

CADILLAC STS
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DWCBUBBA
  • MEMBER
  • 1 POST
I have several DTC codes (1997 STS)
P0404, P0420, P0741, and P1660

How do i trouble shoot these codes and what do I need to do to correct them?
Mar 2, 2007 at 11:57 PM
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CHEVY22
  • ✓Experienced Mechanic
  • 1,375 POSTS
hi
p0404 is a generic egr fault , p0420 is twc system low efficiency ,this could be a multiple items , 02 sensors , backed up converter ,p1660 is the cooling fan control circuit this could be firing to the fan or the fan , fan relay or incorrect ground in the pcm ,and the p0741 is the torque converter clutch is stuck off , this will most likely be an overhaul of the transmission , very common , sorry for the bad news

thanks
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Mar 3, 2007 at 5:07 AM
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