U1003

U1003-ESP CAN C BUS PERFORMANCE







- When Monitored:
With the ignition on.

- Set Condition:
If the Anti-Lock Brake Module detects too many CAN Bus off events on the Dynamics Sensor Data Link circuits.





1. VERIFY DTC IS ACTIVE

NOTE: If present, diagnose and repair DTC U0125-LOST COMMUNICATION WITH DYNAMICS SENSOR before diagnosing this DTC.

1. Turn the ignition on.
2. With the scan tool, read and record the ABS DTCs.
3. With the scan tool, read and record Environmental Data to help identify the conditions in which the DTC was set.
4. With the scan tool, erase the ABS DTCs.
5. Cycle the ignition switch.
6. With the scan tool, read the ABS DTCs.

Does this DTC reset?

Yes

- Go To 2

No

- The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
- Perform the ABS INTERMITTENT CONDITION TEST ABS Intermittent Condition Test.

2. INSPECT RELATED WIRING HARNESS, TERMINALS, AND CONNECTORS
1. Visually inspect the related wiring harness. Look for any pinched, chafed, pierced, and partially broken wires.
2. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, and corroded terminals.

Were any problems found?

Yes

- Repair as necessary.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 3

3. CHECK THE (D465) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR A SHORT TO VOLTAGE




1. Disconnect the Anti-Lock Brake Module harness connector.
2. Disconnect the Dynamics Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (D465) Dynamics Sensor High Data Link circuit.

Is there any voltage present?

Yes

- Repair the (D465) Dynamics Sensor High Data Link circuit for a short to voltage.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 4

4. CHECK THE (D465) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Measure the resistance of the (D465) Dynamics Sensor High Data Link circuit between ground and the Dynamics Sensor harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (D465) Dynamics Sensor High Data Link circuit for a short to ground.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 5

5. CHECK THE (D465) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR AN OPEN




1. Measure the resistance of the (D465) Dynamics Sensor High Data Link circuit between the Dynamics Sensor harness connector and the Anti-Lock Brake Module harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (D465) Dynamics Sensor High Data Link circuit for an open.
- Perform ABS VERIFICATION TEST ABS Verification Test.

6. CHECK THE (D464) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition on.
2. Measure the voltage of the (D464) Dynamics Sensor Low Data Link circuit.

Is there any voltage present?

Yes

- Repair the (D464) Dynamics Sensor Low Data Link circuit for a short to voltage.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 7

7. CHECK THE (D464) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Measure the resistance of the (D464) Dynamics Sensor Low Data Link circuit between ground and the Dynamics Sensor harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (D464) Dynamics Sensor Low Data Link circuit for a short to ground.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Go To 8

8. CHECK THE (D464) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR AN OPEN




1. Measure the resistance of the (D464) Dynamics Sensor Low Data Link circuit between the Dynamics Sensor harness connector and the Anti-Lock Brake Module harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 9

No

- Repair the (D464) Dynamics Sensor Low Data Link circuit for an open.
- Perform ABS VERIFICATION TEST ABS Verification Test.

9. REPLACE DYNAMICS SENSOR AND VERIFY IF DTC IS STILL ACTIVE
1. Replace the Dynamics Sensor. Perform ABS VERIFICATION TEST ABS Verification Test.
2. Turn the ignition on.
3. With the scan tool, erase ABS DTCs.
4. Cycle the ignition switch.

WARNING: Make sure brake capability is available before road testing.

5. Test drive the vehicle by turning the vehicle left or right in a curving manner at a velocity between 6 and 15 mph (10 and 25 km/h).
6. Park the vehicle.
7. With the scan tool, read ABS DTCs.

Does this DTC reset?

Yes

- Replace the Anti-Lock Brake Module.
- Perform ABS VERIFICATION TEST ABS Verification Test.

No

- Test complete.