Mecatronic III

NOTE:
- Perform Inspection and Verification before performing this pinpoint test.
- To clear diagnostic trouble codes (DTC's), refer to Diagnostic Trouble Code, Erasing. Clearing Trouble Codes

C1671-1 Check Power and Ground To Anti-Lock Brake Module
- Turn ignition switch to "OFF".
- Disconnect connector C129 from anti-lock control module.
- Turn ignition switch to "RUN".
- Measure the voltage between ABS control unit C129-1, circuit 31 (BK) and C129-5, circuit 74 (BL).
- Is the voltage greater that 10 volts?
YES - Go to C1671-2.
NO - Go to C1671-3.

C1671-2 Check Anti-Lock Brake Indicator
- Inspect, clean and reconnect C129.
- "START" the vehicle and observe the anti-lock brake indicator.
- Is the indicator illuminated after 5-10 seconds?
YES - Replace anti-lock hydraulic control unit (HCU). Restore vehicle. Retest system.
NO - The fault was intermittent. The ABS should be considered operational at this time and no further action is required. Restore vehicle. Clear DTC's and retest system.

C1671-3 Check Voltage of Circuit 74 (BL)
- Measure the voltage between ABS control module C129-5, circuit 74 (BL), and ground.
- Is the voltage greater that 10 volts?
YES - Service circuit 31 (BK) for an open circuit. Restore vehicle. Clear DTC's and retest system.
NO - Go to C1671-4.

C1671-4 Check Fuse 22 (7.5A) Output
- Turn ignition switch to "RUN".
- Check the output side of fuse 22 (7.5A) cavity for voltage.
- Is the voltage greater that 10 volts?
YES - Service circuit 74 (BL) for open circuit. Restore vehicle. Clear DTC's and retest system.
NO - Go to C1671-5.

C1671-5 Check Circuit 74 (BL) For Short To Ground
- Turn ignition switch to "OFF".
- Remove fuse 22 (7.5A).
- Disconnect C129 from anti-lock brake control module.
- Measure the resistance between ABS control module C129-5, circuit 74 (BL) and ground.
- Is the resistance greater than 10,000 ohms?
YES - Go to C1671-6.
NO - Service circuit 74 (BL) for short to ground. Replace fuse 22 (7.5A). Restore vehicle. Clear DTC's and retest system.

C1671-6 Check Fuse 22 (7.5A) Supply
- Turn ignition switch to "RUN".
- Measure the voltage at the supply side of fuse 22 (7.5A).
- Is the voltage greater that 10 volts?
YES - Replace fuse 22 (7.5A). Restore vehicle. Clear DTC's and retest system.
NO - Go to C1671-7.

C1671-7 Check Circuit 75 (Y) For Voltage
- Leave the ignition switch connected.





- Measure the voltage between ignition switch C279-9, circuit 75 (Y) and ground.
- Is the voltage greater that 10 volts?
YES - Service circuit 75 (Y) for open circuit. Restore vehicle. Clear DTC's and retest system.
NO - Replace ignition switch. Restore vehicle. Clear DTC's and retest system.