Normal Operation
Battery junction box (BJB) fuse 49 (15A) supplies fused ignition voltage to the brake pedal position (BPP) switch, along circuit CBP49 (VT/GY), with the ignition switch in the RUN/START position. With the brake pedal released, the switch is closed and voltage is supplied to the ABS module along circuit CES09 (VT/OG). When the brake pedal is applied, the switch opens and the voltage supply is interrupted.
- DTC B1483 Brake Pedal Input Open Circuit - If during normal operation or the on-demand self test, the ABS module detects an open circuit on the BPP switch circuit, DTC B1483 will be set.
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- BPP switch
- ABS module
The operating voltage required to supply the ABS module, hydraulic pump and isolation valves is in a range between 10 and 16 volts.
Fused battery voltage is supplied to the ABS module from battery junction box (BJB) fuse 10 (30A) along circuit SBB10 (YE/RD) and fuse 8 (40A) along circuit SBB08 (VT/RD). Fused ignition voltage is supplied to the ABS module from smart junction box (SJB) fuse 28 (10A) along CBP19 (BN/WH) and ground is provided to the module along circuit GD123 (BK/GY).
- DTC B1676 Battery Pack Voltage Out of Range - If during normal operation, the vehicle battery voltage becomes less than 9.7 volts for more than 210 ms with vehicle speed greater than 20 km/h (12 mph), or the vehicle battery voltage becomes greater than 18 volts, DTC B1676 will be set. Also, if during the ABS module self-test the vehicle battery voltage becomes higher than 18 volts, DTC B1676 will be set.
This pinpoint test is intended to diagnose the following
- Fuse(s)
- Wiring, terminals or connectors
- Charging system
- ABS module
Active wheel speed sensors generate a square wave signal that is sent to the ABS module. The wheel speed sensor circuitry connects to the ABS module through 2 wires and a connector at each wheel speed sensor. When the ignition switch is turned to the RUN position, the ABS module carries out a self-test by sending a reference voltage through the wheel speed sensors and their circuitry to determine if they are functional.
Voltage and ground signals are supplied to the wheel speed sensors from the ABS module.
| DTC Description | Fault Trigger Condition |
|---|---|
| DTC C1145 RF Wheel Speed Sensor Input Circuit Failure DTC C1155 LF Wheel Speed Sensor Input Circuit Failure DTC C1165 RR Wheel Speed Sensor Input Circuit Failure DTC C1175 LR Wheel Speed Sensor Input Circuit Failure | When the vehicle speed exceeds 5 km/h (3 mph), if the ABS module detects an open, short to ground or voltage or a defective wheel speed sensor input circuit, the appropriate DTC will be set. |
This pinpoint test is intended to diagnose the following
- Wiring, terminals or connectors
- Wheel speed sensor ring (part of the wheel bearing and hub assembly)
- Wheel speed sensors
- ABS module
The wheel speed sensor and sensor ring generate a square wave signal to the ABS module that is proportional to the wheel speed. The ABS module compares the wheel speed inputs from all the wheel speed sensors to determine an impending wheel lockup.
| DTC Description | Fault Trigger Condition |
|---|---|
| DTC C1233 LF Wheel Speed Sensor Signal Fault DTC C1234 RF Wheel Speed Sensor Signal Fault DTC C1235 RR Wheel Speed Sensor Signal Fault DTC C1236 LR Wheel Speed Sensor Signal Fault | When the vehicle speed exceeds 15 km/h (9 mph), if the ABS module does not receive a signal from the wheel speed sensor, the appropriate DTC will be set. These DTCs can also be set by an excessive wheel speed sensor-to-tone ring air gap or a damaged tone ring |
This pinpoint test is intended to diagnose the following
- Mismatched tire sizes
- Wheel speed sensor ring (part of the wheel bearing and hub assembly)
- Wheel speed sensor
- ABS module
The operating voltage required to supply the hydraulic pump motor is in a range between 10 and 16 volts. Fused battery voltage for the hydraulic pump is supplied to the ABS module from battery junction box (BJB) fuse 8 (40A) SBB08 (VT/RD) along circuit SBB08 (VT/RD). Ground for the hydraulic pump is provided through the ABS module along circuit GD123 (BK/GY).
- DTC C1095 ABS Hydraulic Pump Motor Circuit Failure - If the ABS module detects an open circuit, a short to voltage or ground or a defective internal power transistor during normal operation or the ABS module self-test, DTC C1095 will be set. The ABS module will command the pump motor ON for 100 ms (±6 ms), then command the motor OFF and measure the voltage produced by the motor after 6 ms. If the voltage indicates that the motor is spinning at less than 500 rpm there may be a locked motor. If this condition is detected 4 times, then DTC C1095 will be set. The pump motor is also checked for an open circuit 2 seconds after the most recent successful pump motor off command. If the pump motor feedback remains greater than 0.75 volt for more than 50 ms (±6 ms) after these conditions have been met, then DTC C1095 will be set
This pinpoint test is intended to diagnose the following
- Fuse
- Wiring, terminals or connectors
- ABS module
The operating voltage required to supply the ABS module, hydraulic pump and isolation valves is in a range between 10 and 16 volts.
Fused battery voltage is supplied to the ABS module from battery junction box (BJB) fuse 10 (30A) along circuit SBB10 (YE/RD) and fuse 8 (40A) along circuit SBB08 (VT/RD). Fused ignition voltage is supplied to the ABS module from smart junction box (SJB) fuse 28 (10A) along CBP19 (BN/WH) and ground is provided to the module along circuit GD123 (BK/GY).
This pinpoint test is intended to diagnose the following
- Base brake system
- Hydraulic control unit (HCU)