QuestionQUESTION: i have a 1990 cadillac seville i keep getting codes B120 B122 B552 R026 as histroy codes. i have cleared all the codes expect for the r code cause i don't know how. all the codes keep coming back how can i fix all the problems and what do the codes mean? thanks Ray
ANSWER: If all the HISTORY codes are coming back, You are NOT clearing the codes correctly. Disconnecting the battery does NOT erase the codes.
1. re-enter diagnostics and after the codes display you will see ECM?
2. Push and release the LO(v) button and you will see BCM?
3. Push and release the HI button and you will see BCM DATA?.
4. Keep pushing and releasing the LO button until you see BCM CLEAR CODES?
5. Push and release the HI buttons and you will see BCM CODES CLEAR.
6. Wait 3 seconds and push and release the OFF button which should return you to ECM?.
7. Keep pushing and releasing the LO button until you see SIR?
8. Push and release the HI button and you will see SIR CLEAR CODES.
9. Push and release the HI button and you will see in the DRIVERS INFORMATION CENTER this message, HAVE ALL CONDITIONS TO CLEARCURRENT CODES BEEN SATISFIED?
10. Push and release the HI button and you will see SIR CODES CLEAR and the display will go back to ECM?
---------- FOLLOW-UP ----------
QUESTION: tom i cleared the codes like you told me and the b120 b121 b122 codes still come up. what do i need to do to fix this problem?
AnswerQUESTION: Do you have ANYTHING on the dash that could be covering up the light sensor in the dash pad ?.
B120 & B122 = Twilight delay and panel dimming problem.
B121 = Twilight enable switch circuit problem.
In step # 5 of clearing the BCM codes are you seeing the words BCM CODES CLEAR ?.
