P1603
CIRCUIT DESCRIPTION
This diagnostic test checks for the loss of or invalid Sensing/Diagnostic Module (SDM) serial data to the PCM. When such a condition exists for 1 second, DTC P1603 is set.
CONDITIONS FOR SETTING THE DTC
Test Conditions
^ DTC P0322 not set.
^ Engine speed 500 RPM or more for 10 seconds continuously.
Failure Condition
Invalid or no serial data from the SDM to the PCM for 1 second.
ACTION TAKEN WHEN THE DTC SETS
^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ No message will be displayed.
CONDITIONS FOR CLEARING THE DTC
^ A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test.
^ A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
^ PCM battery voltage is interrupted.
^ Using a Scan tool.