GM Service Manual Online
For 1990-2009 cars only

Circuit Description

This diagnostic test checks for absent or invalid Electronic Brake and Traction Control Module (EBTCM) serial data to the PCM. When such a condition exists for 11 seconds, DTC P1602 is set.

Conditions for Setting the DTC

Invalid or no serial data from the EBTCM to the PCM for 11 seconds.

Action Taken When the DTC Sets

    • The powertrain control module (PCM) stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

Conditions for Clearing the MIL/DTC

    • A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
    • A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
    • Use a scan tool in order to clear the MIL/DTC.
    • Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes.

Step

Action

Value(s)

Yes

No

1

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

--

Go to Diagnostic System Check - ABS in Antilock Brake System Delco VI or Diagnostic System Check - ABS in Antilock Brake System Bosch 5.3

Go to Powertrain On Board Diagnostic (OBD) System Check