I read the code stuff up above about what the codes mean, but could not find information on what year, makes and models started using the code computer.

Does my 79 Eldorado give codes?

 

No. On-Board is on DFI engines in Cadillacs 1980 and later. Engines would be 368 or 6.0L with FI, HT4100, 4.5L, 4.9L, or Northstar. 1975-80 EFI has no self diagnostic capabilities. Also On-Board is not available on 1986-92 Fleetwood Brougham, Cimmaron, Catera - all, CTS, XLR, 05 and later STS, 06 and later DTS or any of the SUVs.

 

manual troubleshooting, gotta love it. Thanks for more of the great info slow