Here is the solution to a common problem with HP tuners failing to write your file...
The issue is not with any HPTuners device, nor is it a hardware or software problem with the PCM itself.
The real problem lies in the vehicle wiring. The PCM is designed to receive two switched ignition power feeds from the ignition switch — one on Pin 11 and one on Pin 12.
However, on many early 2004 models, Pin 12 is missing its wire entirely. Here is a photo of a 2004 SRT-4 PCM connector (courtesy of Evolutionoftime25) showing the Dark Blue/Red wire present in Cavity 11, with nothing in Cavity 12.
This missing wire is the reason early 2004 PCMs across the Chrysler lineup often fail to write or flash properly. It appears a cost-saving decision was made to delete what was thought to be a redundant wire. Chrysler’s eventual “fix” was to revise later PCMs so they could function with only the single power wire on Pin 11, rather than reworking the millions of wiring harnesses already in the field.
Solution:
Add a wire to Cavity 12 and splice it together with the existing wire in Cavity 11. This restores proper power during flashing.
For those who flash PCMs on the bench, be sure to add this wire to your bench harness as well.
This simple modification resolves the flashing issues on these early PCMs.
I hope this helps!
Mark
The issue is not with any HPTuners device, nor is it a hardware or software problem with the PCM itself.
The real problem lies in the vehicle wiring. The PCM is designed to receive two switched ignition power feeds from the ignition switch — one on Pin 11 and one on Pin 12.
However, on many early 2004 models, Pin 12 is missing its wire entirely. Here is a photo of a 2004 SRT-4 PCM connector (courtesy of Evolutionoftime25) showing the Dark Blue/Red wire present in Cavity 11, with nothing in Cavity 12.
This missing wire is the reason early 2004 PCMs across the Chrysler lineup often fail to write or flash properly. It appears a cost-saving decision was made to delete what was thought to be a redundant wire. Chrysler’s eventual “fix” was to revise later PCMs so they could function with only the single power wire on Pin 11, rather than reworking the millions of wiring harnesses already in the field.
Solution:
Add a wire to Cavity 12 and splice it together with the existing wire in Cavity 11. This restores proper power during flashing.
For those who flash PCMs on the bench, be sure to add this wire to your bench harness as well.
This simple modification resolves the flashing issues on these early PCMs.
I hope this helps!
Mark
