Malibu L4-2.4L (2010)
‹› If greater than the specified range, test the serial data circuit for a short to voltage, refer to Testing the Serial Data Circuit for a Short to
Voltage.
5. Ignition OFF for 60 seconds, test for greater than 100 ohm between the serial data circuit terminal 1 and ground.
‹› If less than the specified range, test the serial data circuit for a short to ground, refer to Testing the Serial Data Circuits for a Short to ground.
6. Disconnect the appropriate harness connector at the BCM.
7. Test for less than 2 ohm between the DLC serial data circuit terminal 1 and the BCM connector.
‹› If greater than the specified range, test the serial data circuit for an open/high resistance. If the circuits test normal, replace the BCM.
Testing the Serial Data Circuits for a Short to Voltage
1. Ignition OFF, disconnect the appropriate harness connectors at the BCM.
2. Ignition ON, test for less than 4.5 V between the DLC serial data circuit terminal 1 and ground.
‹› If greater than the specified range, repair the short to voltage.
3. Test for less than 4.5 V between each serial data circuit at the BCM connectors and ground.
‹› If greater than the specified range, perform the appropriate test listed below:
*
Serial data circuits with one control module, test the serial data circuit for a short to voltage. If the circuit tests normal replace the control
module.
*
Serial data circuits with 2 or more control modules, test each section of the serial data circuit for a short to voltage. If the circuits test normal,
replace the control module that causes the short to voltage when connected.
Testing the Serial Data Circuits for a Short to Ground
1. Ignition OFF, disconnect the appropriate harness connectors at the BCM.
2. Test for infinite resistance between the DLC serial data circuit terminal 1 and ground.
‹› If not the specified value, repair the short to ground.
3. Ignition OFF for 60 seconds, test for greater than 100 ohm between each serial data circuit and ground.
‹› If less than the specified range, perform the appropriate test listed below:
*
Serial data circuits with one control module, test the serial data circuit for a short to ground. If the circuit tests normal replace the control
module.
*
Serial data circuits with 2 or more control modules, test each section of the serial data circuit for a short to ground. If the circuits test normal,
replace the control module that causes the short to ground when connected.
Testing the Serial Data Circuit for an Open/High Resistance
1. Ignition OFF, disconnect the appropriate harness connectors at the BCM.
2. Install a 3 A fused jumper wire between the disconnected BCM connector DLC terminal and a low speed GMLAN serial data circuit terminal that
is not communicating.
3. Ignition ON, verify the scan tool communicates with the control modules connected to the low speed GMLAN serial data circuit.
‹› If any control module does not communicate, test each section of the serial data circuit for an open/high resistance. If the circuits test normal,
replace the control module that does not communicate when connected.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Testing and Inspection/Diagnostic Trouble Code Tests and Associated Procedures/Verification Tests
and Procedures) after completing the repair.
*
GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Wiring Repairs/GMLAN Wiring Repairs)
*
Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming
Scan Tool Does Not Power Up
Scan Tool Does Not Power Up
