Diagnosis & Testing: Notes
NOTE:
Tech 1 Scan Tester (94-00101-A) and Adapter (T-100) are required to diagnose ABS-VI.
- Before diagnosing ABS system for fault codes, perform pre-diagnostic visual inspection to detect obvious problems. See PRE-DIAGNOSTIC INSPECTION under DIAGNOSIS & TESTING . Repair problems as necessary.
- Using Tech 1, read all current and history fault codes. Fault codes are stored in order of occurrence. If no fault codes are present, go to step 3). If fault codes are stored, note which codes are current and which codes are history. DO NOT clear fault codes.
- Using Tech 1, review code history. Review fault codes stored and frequency of failure. Refer to ENHANCED DIAGNOSTICS under DIAGNOSIS & TESTING . DO NOT clear codes until ABS system repairs are complete. After reviewing ENHANCED DIAGNOSTICS, perform DIAGNOSTIC CIRCUIT CHECK under DIAGNOSTIC CHARTS . Reference ABS FAULT CODES table as necessary.
- Using Tech 1, perform automated modulator test. Automated modulator test may isolate cause of problem. If failure is intermittent and not reproducible, test drive vehicle using snapshot feature of Tech 1. Drive vehicle in a normal manner, with normal acceleration, stopping and turning.
- If vehicle test drive does not reproduce any failures, perform another test drive. On second test drive, perform an ABS stop from approximately 30-50 MPH. Check snapshot feature of Tech 1 to see if any faults were set.
- If fault codes were set, perform DIAGNOSTIC CIRCUIT CHECK under DIAGNOSTIC CHARTS . Reference ABS FAULT CODES table as necessary. DO NOT clear codes until ABS system repairs are complete. If no faults were set and ABS warning light and/or BRAKE warning light is on, refer to CHART A or CHART B under DIAGNOSTIC CHARTS .
ABS FAULT CODES
| Code | Definition | ||
|---|---|---|---|
| A011 | ABS Warning Light Circuit Open Or Shorted To Ground | ||
| A013 | ABS Warning Light Circuit Shorted To Battery | ||
| A014 | Enable Relay Contacts Or Fuse Open | ||
| A015 | Enable Relay Contacts Shorted To Battery | ||
| A016 | Enable Relay Coil Circuit Open | ||
| A017 | Enable Relay Coil Circuit Shorted To Ground | ||
| A018 | Enable Relay Coil Circuit Shorted To Battery | ||
| A021 | Left Front Wheel Speed Is Zero | ||
| A022 | Right Front Wheel Speed Is Zero | ||
| A023 | Left Rear Wheel Speed Is Zero | ||
| A024 | Right Rear Wheel Speed Is Zero | ||
| A025 | Excessive Left Front Wheel Speed Variation | ||
| A026 | Excessive Right Front Wheel Speed Variation | ||
| A027 | Excessive Left Rear Wheel Speed Variation | ||
| A028 | Excessive Right Rear Wheel Speed Variation | ||
| A031 | Two Wheel Speeds Are Zero | ||
| A032 | Left Front Wheel Sensor Shorted To Battery Or Ground | ||
| A033 | Right Front Wheel Sensor Shorted To Battery Or Ground | ||
| A034 | Left Rear Wheel Sensor Shorted To Battery Or Ground | ||
| A035 | Right Rear Wheel sensor Shorted To Battery or Ground | ||
| A036 | System Voltage Low | ||
| A037 | System Voltage High | ||
| A038 | (1) Left Front ESB Will Not Hold Motor | ||
| A041 | (1) Right Front ESB Will Not Hold Motor | ||
| A042 | (1) Rear Axle ESB Will Not Hold Motor | ||
| A044 | Left Front Channel Will Not Move | ||
| A045 | Right Front Channel Will Not Move | ||
| A046 | Rear Axle Channel Will Not Move | ||
| A047 | Left Front Motor Spins Freely | ||
| A048 | Right Front Motor Spins Freely | ||
| A051 | Rear Axle Motor Spins Freely | ||
| A052 | Left Front Channel In Release Too Long | ||
| A053 | Right Front Channel In Release Too Long | ||
| A054 | Rear Axle Channel In Release Too Long | ||
| A055 | Motor Driver Fault Detected | ||
| A056 | Left Front Motor Circuit Open | ||
| A057 | Left Front Motor Circuit Shorted To Ground | ||
| A058 | Left Front Motor Circuit | ||
| *** | Shorted To Battery Or Motor Shorted | ||
| A061 | Right Front Motor Circuit Open | ||
| A062 | Right Front Motor Shorted To Ground | ||
| A063 | Right Front Motor Shorted To Battery | ||
| A064 | Rear Axle Motor Circuit Open | ||
| A065 | Rear Axle Motor Circuit Shorted To Ground | ||
| A066 | Rear Axle Motor Circuit | ||
| *** | Shorted To Battery Or Motor Shorted | ||
| A076 | Left Front Solenoid Circuit | ||
| *** | Open Or Shorted To Battery | ||
| A077 | Left Front Solenoid Circuit Shorted | ||
| *** | To Ground Or Driver Circuit Open | ||
| A078 | Right Front Solenoid Circuit | ||
| *** | Open Or Shorted To Battery | ||
| A081 | Right Front Solenoid Circuit | ||
| *** | Shorted To Ground Or Driver Circuit Open | ||
| A082 | Calibration Memory Failure | ||
| A086 | Red BRAKE Warning Light Activated By EBCM | ||
| A087 | Red BRAKE Warning Light Circuit Open | ||
| A088 | Red BRAKE Warning Light Circuit | ||
| *** | Shorted To Battery | ||
| A091 | Open Brake Switch Contacts | ||
| *** | During Deceleration | ||
| A092 | Open Brake Switch Contacts | ||
| *** | When ABS Was Required | ||
| A093 | Code A091 Or A092 Set In | ||
| *** | Last Or Current Ignition Cycle | ||
| A094 | Brake Switch Contacts Always Closed | ||
| A095 | Brake Switch Circuit Open | ||
| A096 | Brakelight Circuit Open | ||
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