Toyota 30C28100.cuw Engine Control Calibration
Learn how Toyota calibration 30C28100 relates to a 2004 Tundra engine control update for oxygen sensor diagnostic codes P0136 and P0156.
30C28100.cuw is associated with an updated engine control calibration for the 2004 Toyota Tundra. Toyota service bulletin EG012-05 identifies calibration 30C28100 in connection with a malfunction indicator light and diagnostic trouble codes P0136 and P0156.
What the calibration controls
The engine control module manages engine operation and monitors emissions-related components. Oxygen sensors provide information to that system, while onboard diagnostics check the sensor circuits and illuminate the malfunction indicator light when a qualifying fault is detected.
P0136 and P0156 concern the oxygen sensor circuits for sensor 2 on banks 1 and 2, respectively. These are downstream sensor locations, after the catalytic converters. The bulletin identifies 30C28100 as an updated calibration for the warning-light condition associated with those codes.
Practical significance
For a 2004 Tundra displaying either code, the calibration is relevant to the diagnostic context documented by Toyota. The codes point to monitored oxygen sensor circuits, but they do not by themselves establish which component has failed.
The service record identifies the updated calibration and its bulletin topic. It does not specify the detailed software changes or establish that every 2004 Tundra uses this calibration.