My CEL just recently came on, with the addition of the dreaded P0106 code, my car also threw an ABS code C1203. My car brakes and stops just fine, and my ABS light isn't on. And there doesn't seem to be a thread on it currently. Anyone have any input on this error code? Car is a 2011 G37x with 82K miles.

 

I believe that C code may be a speed sensor issue, and that P code hopefully is just a vacuum leak that you can trace.
G/L

 

Here is what i have:

P0106 MANIFOLD ABSOLUTE PRESSURE SENSOR
-Manifold absolute pressure (MAP) circuit range/performance

There is a TSB that might fix your issue:
http://www.infinitig37.com/TSB/ITB12-026a.pdf


C1203:
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Description
Transmits the following signals via CAN communication to AWD control unit.
• Vehicle speed signal
• Stop lamp switch signal (brake signal)

What scan tool did you use to find the "C1203?" If the ABS light is not on, it may be an old code.