What is Code 12

[Ramit-77]

What does engine trouble code 12 mean. Thanks.

[Challenger]

Ramit 77
Trouble Code 12 is just a code to let you know that you are in the code retrieving diagnostic. Anything higher than that will be your actual trouble codes. Im a GM tech our GM cars start out with code 12 also.

[rb77413]

I have to disagree. In a MoPar a code 12 means that you have lost power to the computer. Probably disconnecting the battery. Unlike a GM, us MoPar guys with newer cars get a code 55. This is the code that is given at the end of the diagnostic codes. Nothing against the GM guy. Just thats how MoPars are. At least he tried to help. All the codes are listed in the service manual. You probably had a 12 and 55 if nothing is wrong.

[Challenger]

rb77413
Evidently I dont understand something about your statements. If Ive lost power to the computer than how can I get a code 12 when the computer has no power? Also you say that you probably have a 12 and a 55 if nothing is wrong. WHAT! I thought you just said that code 12 was a lost power code. Im confused.

[ChristianCuda]

Code 12 set if power was lost to the PCm withing the last fifty ignition cycles. This will not set the check engine light on though. This code will set in the computer after disconnecting the battery this code automatically sets. After 50 ignition cycles if the battery has not been disconnected and there have been no other problems with power then this codes goes away. Code 55 is end of code squence telling you that it has given you all the codes in the computer. If you dont have any codes set in the computer it will still give you a code 55 telling you that you are at the end of the code list. Atleast you know there are no codes when you get the code 55. If you just didnt get anything then you would think something might be wrong.

Christian


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68 'Cuda 383 Formula S recreation
Working on adding EFI
69 'Cuda Race Parts Car
76 Duster 273 recent transplant
95 Neon 2.0 SOHC best of 16.96
84 Dodge Ram D50 transplanting 360

[rb77413]

Sorry about that Challenger. I can't type as fast as i'm thinking, so i kinda left so details out. ChristianCuda said what I was trying to spit out.