2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 2030

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 2030

瀚慖f 35-50 ohm there may be a third terminating resistor between the serial data circuits. This can happen if the incorrect control module is

installed. Some control modules are available with and without the terminating resistors installed to reduce the need of terminating

resistors in the wiring harness.

瀚慖f greater than 70 ohm but less than infinite, test the serial data circuit for an open/high resistance. Refer to Testing the Serial Data

Circuits for an Open/High Resistance.

瀚慖f infinite, test the serial data circuits between the DLC and the first connection to the serial data circuit for an open/high resistance.

7. If the circuits test normal, refer to Testing the Ignition Circuit.

Testing the Serial Data Circuits for a Short to Voltage

1. Ignition OFF, disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at an easily accessible control

module.

2. Ignition ON, test for greater than 3 V between the serial data circuits and ground. Verify that one or more serial data circuits are greater than

3 V.

瀚慖f less than the specified range for all serial data circuits, replace the control module that was disconnected.

3. Ignition OFF, disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at another control module, in the

direction of the circuit shorted to voltage.

4. Ignition ON, test for greater than 3 V between the serial data circuits and ground. Verify that one or more serial data circuits are greater than

3 V.

瀚慖f less than the specified range for all serial data circuits, replace the control module that was just disconnected.

5. Repeat step 3 until one of the follow conditions are isolated:

* A short to voltage on the serial data circuit between 2 control modules

* A short to voltage on the serial data circuit between a control module and a terminating resistor

Testing the Serial Data Circuits for a Short to Ground

1. Ignition OFF, disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at an easily accessible control

module.

2. Ignition OFF for 60 seconds, test for less than 100 ohm between the serial data circuits and ground. Verify that one or more serial data

circuits are less than 100 ohm.

瀚慖f greater than the specified range for all serial data circuits, replace the control module that was disconnected.

3. Disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at another control module, in the direction of

the circuit shorted to ground.

4. Ignition OFF for 60 seconds, test for less than 100 ohm between the serial data circuits and ground. Verify that one or more serial data

circuits are less than 100 ohm.

瀚慖f greater than the specified range for all serial data circuits, replace the control module that was just disconnected.

5. Repeat step 3 until one of the follow conditions are isolated:

* A short to ground on the serial data circuit between 2 control modules

* A short to ground on the serial data circuit between a control module and a terminating resistor

Testing the Serial Data Circuits for a Short between the Circuits

1. Ignition OFF, disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at an easily accessible control

module, that is not communicating.

2. Ignition OFF for 60 seconds, test for less than 110 ohm between each pair of serial data circuits. Verify that one pair of serial data circuits are

less than 110 ohm.

瀚慖f greater than the specified range for each pair of serial data circuits, replace the control module that was disconnected.

3. Connect the harness connectors at the control module that was disconnected.

4. Disconnect the harness connectors with the mid speed or chassis high speed serial data circuits at another control module, in the direction of

the circuits shorted together.

5. Ignition OFF for 60 seconds, test for less than 110 ohm between each pair of serial data circuits. Verify that one pair of serial data circuits are

less than 110 ohm.

瀚慖f between the specified range for each pair of serial data circuits, replace the control module that was just disconnected.

6. Repeat step 3 until one of the following conditions are isolated:

* Serial data circuits shorted together between 2 control modules

* Serial data circuits shorted together between a control module and a terminating resistor

* A shorted terminating resistor