U1004

U1104-CAN C BUS CRC PERFORMANCE





When Monitored
With the ignition on.

Set Condition
If the Anti-Lock Brakes Module detects an invalid CAN message from the Dynamics Sensor.

Possible Causes
- WIRING HARNESS, TERMINAL, CONNECTOR DAMAGE
- (D52) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT SHORTED TO GROUND, VOLTAGE, OR OPEN
- (D51) DYNAMICS SENSOR LOW DATA LINK CIRCUIT SHORTED TO GROUND, VOLTAGE, OR OPEN
- DYNAMICS SENSOR INSTALLATION
- DYNAMICS SENSOR
- ANTI-LOCK BRAKES MODULE

Diagnostic Test
1. VERIFY DTC IS ACTIVE
Turn the ignition on.
With the scan tool, read and record ABS DTCs.
With the scan tool, read and record Environmental Data (EV Data).
With the scan tool, erase ABS DTCs.
Cycle the ignition switch.
With the scan tool, read ABS DTCs.
Does this DTC reset?
Yes >> Go To 2.
No >> Perform the ABS Intermittent Condition diagnostic procedure. Component Tests and General Diagnostics
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
2. CHECK THE DYNAMICS SENSOR INSTALLATION

NOTE: Dynamics Sensor installation and mounting bolt torque is crucial for proper operation.

Turn the ignition off.
Check the Dynamics Sensor for damaged, modified, and bent mounting brackets.
Check the Dynamics Sensor mounting bolts for a loose or over tightened condition.
Were any problems found?
Yes >> Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Go To 3.
3. INSPECT RELATED WIRING HARNESS, TERMINALS, & CONNECTORS
Visually inspect the related wiring harness. Look for any pinched, chafed, pierced, and partially broken wires.
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 - VER 1. ABS Verification Test
No >> Go To 4.
4. CHECK THE (D52) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR A SHORT TO VOLTAGE





Disconnect the Anti-Lock Brakes Module harness connector.
Disconnect the Dynamics Sensor harness connector. Turn the ignition on.
Measure the voltage of the (D52) Dynamics Sensor High Data Link circuit.
Is there any voltage present?
Yes >> Repair the (D52) Dynamics Sensor High Data Link circuit for a short to voltage.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Go To 5.
5. CHECK THE (D52) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR A SHORT TO GROUND





Turn the ignition off.
Measure the resistance of the (D52) Dynamics Sensor High Data Link circuit between ground and the Dynamics Sensor harness connector.
Is the resistance below 5.0 ohms?
Yes >> Repair the (D52) Dynamics Sensor High Data Link circuit for a short to ground.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Go To 6.
6. CHECK THE (D52) DYNAMICS SENSOR HIGH DATA LINK CIRCUIT FOR AN OPEN





Measure the resistance of the (D52) Dynamics Sensor High Data Link circuit between the Dynamics Sensor harness connector and the AntiLock Brakes Module harness connector.
Is the resistance below 5.0 ohms?
Yes >> Go To 7.
No >> Repair the (D52) Dynamics Sensor High Data Link circuit for an open.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
7. CHECK THE (D51) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR A SHORT TO VOLTAGE





Turn the ignition on.
Measure the voltage of the (D51) Dynamics Sensor Low Data Link circuit.
Is there any voltage present?
Yes >> Repair the (D51) Dynamics Sensor Low Data Link circuit for a short to voltage.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Go To 8.
8. CHECK THE (D51) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR A SHORT TO GROUND





Turn the ignition off.
Measure the resistance of the (D51) Dynamics Sensor Low Data Link circuit between ground and the Dynamics Sensor harness connector.
Is the resistance below 5.0 ohms?
Yes >> Repair the (D51) Dynamics Sensor Low Data Link circuit for a short to ground.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Go To 9.
9. CHECK THE (D51) DYNAMICS SENSOR LOW DATA LINK CIRCUIT FOR AN OPEN





Measure the resistance of the (D51) Dynamics Sensor Low Data Link circuit between the Dynamics Sensor harness connector and the AntiLock Brakes Module harness connector.
Is the resistance below 5.0 ohms?
Yes >> Go To 10.
No >> Repair the (D51) Dynamics Sensor Low Data Link circuit for an open.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
10. REPLACE DYNAMICS SENSOR & VERIFY IF DTC IS STILL ACTIVE
Replace the Dynamics Sensor.
Turn the ignition on.
With the scan tool, erase ABS DTCs.
Cycle the ignition switch.

WARNING: Ensure brake capability is available before road testing.

Test drive the vehicle by turning the vehicle left or right in a curving manner at a velocity between 10 and 25 km/h (6 and 15 m.p.h.).
Park the vehicle.
With the scan tool, read ABS DTCs.
Does this DTC reset?
Yes >> Replace the Anti-Lock Brakes Module.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
No >> Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test