Impala V8-5.3L (2008)
^
If less than the specified value, test the serial data circuits for a short between them.
8. Test for less than 2 ohms of resistance in the GMLAN serial data circuit between the DLC terminal 6 and BCM terminal 16.
^
If greater than the specified range, test the GMLAN serial data circuit for open/high resistance.
9. Ignition OFF, connect the terminator resistor, and disconnect the harness connector X 4 of the BCM.
10. Verify a test lamp illuminates between each ground circuit terminal of the BCM listed below and B+.
*
X 3 terminal 1
*
X 3 terminal 5
*
X 4 terminal 9
^
If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
11. Ignition ON, verify a test lamp illuminates between each B+ circuit terminal of the BCM listed below and ground.
*
X 4 terminal 1
*
X 4 terminal 3
*
X 4 terminal 4
^
If the test lamp does not illuminate, test the B+ circuit for an open/high resistance or short to ground.
12. Connect the harness connectors of the BCM.
13. Ignition OFF, disconnect the harness connector of the ECM as listed:
*
RPO LS4 - X3
*
RPO LZE, LZ4 or LZ8 - X1
14. Attempt to communicate with the BCM. Communication should not be available.
^
If communication is established, replace the ECM.
15. Ignition OFF, disconnect the harness connector of the TCM.
16. Attempt to communicate with the BCM. Communication should not be available.
^
If communication is established, test the serial data circuits for a short between the circuits, short to voltage, or a short to ground between the
TCM and the ECM. If the circuits test normal, replace the TCM.
17. Ignition OFF, disconnect the harness connector of the EBCM, if equipped. Attempt to communicate with the BCM. Communication should not be
available.
^
If communication is established, test the serial data circuits for a short between the circuits, short to voltage, or a short to ground between the
EBCM and the TCM. If the circuits test normal, replace the EBCM.
18. Ignition OFF, disconnect the harness connector X3 of the BCM.
19. Ignition ON, test for less than 1 volt between the serial data circuits of BCM terminal 8 and ground, and between BCM terminal 9 and ground.
^
If greater than the specified range, test the circuit for a short to voltage.
20. Test for infinite resistance between the serial data circuits of BCM terminal 8 and ground, and between BCM terminal 9 and ground.
^
If less than the specified value, test the circuit for a short to ground.
21. Test for infinite resistance between the serial data circuits of BCM terminal 8 terminal 9.
^
If less than the specified value, test the serial data circuits for a short between them.
22. If the circuits test normal, replace the BCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair. See: Testing and Inspection/Diagnostic Trouble Code Tests and Associated
Procedures/Verification Tests and Procedures