Pinpoint Test G : C0020:16, C0020:17, C0020:49: Notes
Refer to Vehicle Dynamic Systems for schematic and connector information.
Normal Operation and Fault Conditions
The ABS module uses an internal solid state switch to operate the hydraulic pump motor. The ABS module tests the hydraulic pump motor by activating it for 30 milliseconds. While the pump motor is activated, the ABS module monitors the voltage drop across the hydraulic pump motor. After 30 milliseconds have passed, the ABS module stops applying voltage to the pump motor and monitors the voltage the spinning hydraulic pump motor is generating and the voltage drop across the hydraulic pump motor solid state switch. If the monitored voltages are not within specifications, the ABS module sets a DTC.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| C0020:16 | ABS Pump Motor Control: Circuit Voltage Below Threshold | This DTC sets if the ABS module detects an under voltage condition at the pump motor voltage input. |
| C0020:17 | ABS Pump Motor Control: Circuit Voltage Above Threshold | This DTC sets on-demand if the ABS module detects a pump motor voltage input greater than 17 volts for more than 0.5 seconds. |
| C0020:49 | ABS Pump Motor Control: Internal Electronic Failure | This DTC sets if the hydraulic pump motor actual state does not match the commanded state for 30 seconds; pump is running, pump is not running or pump motor relay shorted. |
Possible Causes
- Fuse
- Wiring, terminals or connectors
- Vehicle battery and charging system
- HCU
- ABS module
Visual Inspection and Diagnostic Pre-checks
- Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
- Make sure the vehicle battery terminals are tightened to their correct torque specifications.
- Make sure BJB fuse 52 (60A) and the fuse socket are OK.