Diagnostic Aids

This test is only intended to diagnose:

• Malfunction of ABS CM.
• Poor connection or open in request signal circuit between PCM and ABS CM.

1. Connect NGS scan tool to Data Link Connector (DLC). Using scan tool, perform PID/DATA MONITOR PROCEDURE  . Select PID MMI SIGNAL. Start and operate engine at idle. If duty ratio is 93-97 percent, go to next step. If duty ratio is not 93-97 percent, go to step  4 .
2. Turn ignition switch to OFF position. Disconnect ABS CM harness connector. Turn ignition switch to ON position (engine off). Measure voltage between ABS CM harness connector terminals "X" (Brown/White wire) and "D" (Black wire). See WIRING DIAGRAMS  . If voltage is 5 volts or more, go to next step. If voltage is less than 5 volts, repair open or short to ground in Brown/White wire between ABS CM and PCM.
3. Backprobe PCM harness connector terminals No. 11 (Brown/White wire) and 91 (Black/Yellow wire). See WIRING DIAGRAMS  . Check duty ratio between these terminals with engine at idle. Duty ratio should be 70-99 percent or 0.9-27 degrees if using a dwell meter set at 4-cycle/4-cylinder. If duty ratio is as specified, replace PCM. If duty ratio is not as specified, replace ABS CM.
4. Reconnect all connectors, clear DTCs and recheck system operation. See CLEARING CODES  in DIAGNOSIS & TESTING. If DTC C1118 is reset, replace ABS CM. If DTC C1118 does not reset, problem was a temporary poor contact in circuit or connector. Repair as necessary.