GM Service Manual Online
For 1990-2009 cars only

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 Running the DTC

    •  DTC P0322 not set.
    •  Engine speed 500 RPM or more for 10 seconds continuously.

Conditions for Setting the DTC

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.
    • Use a scan tool to clear DTCs.
    • Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in Powertrain Control Module Description .

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to SIR Diagnostic System Check in SIR

Go to Powertrain On Board Diagnostic (OBD) System Check