About a week and a half ago I pulled a code 51 from my car.
CODE 51
Trouble Code 51 indicates that the ECM sensed a fault in the PROM.
When the PROM was initially created, a checksum number representing the total of all the cell values was also stored. The ECM uses this checksum as one way to determine if the contents of any cell has changed. A Code 51 causes the ECM to enter Back-Up mode which uses the CALPAK for default sensor values.
The conditions for setting this code are:
power has just been applied to the ECM, and
the calculated checksum does not match the stored checksum.
- or -
the engine was just started, and
either of two specific PROM locations do not contain the expected value. (One location should have 1's in the odd numbered bits and the other has 1's in the even numbered bit positions.)
Typical causes for this code include:
1) Incorrectly installed PROM module
2) Defective PROM module
3) Defective ECM
So I ordered a new ECM and CALPAK after checking my original ECM, PROM, CALPAK and the harness going into the ECM. Well, tonight I installed the new ECM and CALPAK and after 2 minutes of warming up the car it threw the SES light again. So I went to check the code again and it was code 51. So, I cleared the code and the car ran fine and no codes being shown. So we took it for a spin down the road about 3 miles of just easy riding (no quick accel or boost being shown). The car still ran great with no signs of the SES light. Well we decided to ease into it about 5 psi and the SES light shows up. So we took it back to the house and pulled multiple code :11, 13,14,22,24,42,45,and again the dreaded 51. Here is the link to what these codes are http://www.gnttype.org/maint/malf.html. Can someone please shed some light on what I need to do cause I don't want to throw out more money to find out that it wont fix the problem. Thanks in adavce.
CODE 51
Trouble Code 51 indicates that the ECM sensed a fault in the PROM.
When the PROM was initially created, a checksum number representing the total of all the cell values was also stored. The ECM uses this checksum as one way to determine if the contents of any cell has changed. A Code 51 causes the ECM to enter Back-Up mode which uses the CALPAK for default sensor values.
The conditions for setting this code are:
power has just been applied to the ECM, and
the calculated checksum does not match the stored checksum.
- or -
the engine was just started, and
either of two specific PROM locations do not contain the expected value. (One location should have 1's in the odd numbered bits and the other has 1's in the even numbered bit positions.)
Typical causes for this code include:
1) Incorrectly installed PROM module
2) Defective PROM module
3) Defective ECM
So I ordered a new ECM and CALPAK after checking my original ECM, PROM, CALPAK and the harness going into the ECM. Well, tonight I installed the new ECM and CALPAK and after 2 minutes of warming up the car it threw the SES light again. So I went to check the code again and it was code 51. So, I cleared the code and the car ran fine and no codes being shown. So we took it for a spin down the road about 3 miles of just easy riding (no quick accel or boost being shown). The car still ran great with no signs of the SES light. Well we decided to ease into it about 5 psi and the SES light shows up. So we took it back to the house and pulled multiple code :11, 13,14,22,24,42,45,and again the dreaded 51. Here is the link to what these codes are http://www.gnttype.org/maint/malf.html. Can someone please shed some light on what I need to do cause I don't want to throw out more money to find out that it wont fix the problem. Thanks in adavce.