Need Help With Codes....

SCchick3

Registered User
I have a '91 SC that I just got running and i have about 6 codes that I need help with. I dont have a service manual so if anyone knew what these codes were, I would appreciate the help :)

Code 17

Code 19

Code 42

Code 21

Code 23

Code 27
 
SC specific codes are here....use these only:

http://www.njtacc.com/tech/eec_codes.html

Many of the codes you list indicate the engine was not at operating temperature prior to running tests. Get it fully warmed first, then do the tests in order. Don't bother testing until this can be done.

KOEO
KOER

Always troubleshoot codes in order starting from the lowest ##.

O=Key On Engine Off (KOEO) (codes with engine off)
C=Continuous Memory (codes stored when engine was running)
R=Engine Running (codes produced as engine is running)
 
Some info is just plain wrong here...

First, there is no such thing as SC only codes except for codes that may be specific to a system or component that only appears on an SC.

Second, you must FIRST determine if these code are HARD FAULTS or CONTINUOUS MEMORY codes. This is done by recording the codes before and after the SEPARATOR CODE (10). Example you get 12 43 10 21 34... The codes BEFORE the 10 are hard faults, the codes after are memory. This is important because a hard fault is a problem the EEC sees right now when the test was run, while a memory code is something that happened sometime within the last 40 warm-up cycles.

It is also important to know whether the codes are KOEO or KOER. These stand for Key On Engine Off & Key On Engine Running.

If a hard fault is identified as KOEO, it is an electrical problem as the engine isn't running. The only exceptions to this are TP and EGR codes where a mechanical problem can cause a reading to be out of range for the test. Example: a fleck of carbon is sticking the EGR valve open causing the reading to be out of range, or a similar condition with the throttle causing the same.

Finally, you ALWAYS start with the FIRST CODE GENERATED, not the lowest number!!!!! Cannot emphasize that enough!!!! The first code generated can & does cause additional codes that are of no use after the INITIAL problem is found & corrected!! EEC spits the codes out in ascending order, not occuring order.

The proper way to diagnose ANY code related problem is to record all codes present & then erase them and rerunn the test(s) to determine the first code. You then follow the diagnostics for that code to repair.

Additionally, you should run KOEO first. Only run KOER if there are no codes KOEO. The rational for this is simple: If there is an electrical problem with something, how can it be expected to operate correctly from a mechanical standpoint?

Hope this info is useful.
 
>First, there is no such thing as SC only codes except for codes that may be specific to a system or component that only appears on an SC.

No one said anything different. Relax. Let's try to help the OP with their specific issues.

>Finally, you ALWAYS start with the FIRST CODE GENERATED, not the lowest number!!!!


Same thing in my experience. The advice is to be methodical, in any case, and not jump around by perhaps focusing on one code and gleefully ignoring the others.
 
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?????

While I'm completely relaxed, you might want to reread your previous post. You gave specific information that you now indicate was never stated and may not actually be accurate. My post was for the specific purpose of helping OP and nothing there is inaccurate, incorrect, incomplete or misleading...:D
 
While I'm completely relaxed, you might want to reread your previous post. You gave specific information that you now indicate was never stated and may not actually be accurate. My post was for the specific purpose of helping OP and nothing there is inaccurate, incorrect, incomplete or misleading...:D

Well, you're drinking from a different cup - what can I say except have a nice day.
 
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