Test B: Main Relay Failure
NOTE:
This test is associated with DTC C1185.
- Check Voltage At Pin No. 17
- Measure and record battery voltage. Disconnect ABS control module 40-pin connector (located on left side of engine compartment). Install Breakout Box (014-00322) with proper overlay. Connect a jumper wire between breakout box pins No. 19 and 14. Turn ignition switch to RUN position. Measure voltage between breakout box pins No. 17 and 1. If voltage is 10-18 volts and within .5 volt of recorded battery voltage, go to next step. If voltage is not 10-18 volts or is not within .5 volt of recorded battery voltage, go to step 4) - Verify Code
- Reconnect ABS control module connector. Turn ignition switch to ON position. Check ABS warning light. If light is on, go to next step. If light is off, fault is intermittent. Perform SYMPTOM H: INTERMITTENT DIAGNOSIS PROCEDURE under SYMPTOM TESTS. - Retrieve Codes
- Using New Generation Star (NGS) tester or equivalent, retrieve codes. If DTC C1185 is present, replace ABS control module and go to step 14). If any other codes are present, go to appropriate trouble code test. See TROUBLE CODE DIRECTORY under TROUBLE CODE TESTS. - Check Fuse
- Turn ignition switch to OFF position. Remove and inspect 30-amp ABS fuse, located in power distribution box (located on left side of engine compartment, near fender well). If fuse is okay, go to step 7). If fuse is blown, go to next step. - Check For Short To Ground
- Remove ABS main relay (left side of engine compartment). Measure resistance of Tan/Yellow wire between ground and ABS main relay connector. If resistance is 10 k/ohms or more, go to next step. If resistance is less than 10 k/ohms, repair short to ground in Tan/Yellow wire. Replace 30-amp ABS fuse and go to step 14). - Check For Short To Ground
- Disconnect HCU 8-pin connector. Install Breakout Box (014-00322) with proper overlay. Measure resistance between breakout box pin No. 17 and pins No. 1 (Orange/Yellow wire) and No. 4 (Orange/Yellow wire) at HCU connector. If resistance is less than 10 k/ohms, repair short to ground in Orange/Yellow wire. Go to step 14). If resistance is 10 k/ohms or more, replace ABS main relay and go to step 14). - Check Power To Fuse
- Remove 30-amp ABS fuse from power distribution box. Turn ignition switch to RUN position. Measure voltage between ground and power side of 30-amp fuse cavity. If battery voltage is present, go to next step. If battery voltage is not present, locate and repair open circuit in power feed circuit. Go to step 14). - Check For Open Circuit
- Turn ignition switch to OFF position. Remove ABS main relay. Measure resistance of Tan/Yellow wire between 30-amp fuse holder and ABS main relay connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Tan/Yellow wire. Go to step 14). - Check For Short To Ground
- Turn ignition switch to OFF position. Measure resistance of Pink/Light Green wire between ground and pin No. 19 at breakout box. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, locate and repair short to ground in Pink/Light Green wire and go to step 14). - Check For Open Circuit
- Turn ignition switch to OFF position. Measure resistance of Pink/Light Green wire between main relay connector and pin No. 19 at breakout box. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Pink/Light Green wire and go to step 14). - Check For Open Circuit
- Turn ignition switch to OFF position. Measure resistance of Orange/Yellow wire between main relay connector and pin No. 17 at breakout box. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, locate and repair open circuit in Orange/Yellow wire and go to step 14). - Check Relay Coil
- Remove ABS main relay. Measure resistance between pins No. 85 (Light Blue/Pink wire) and No. 86 (Pink/Light Green wire) at main relay. If resistance is 60-80 ohms, go to next step. If resistance is not 60-80 ohms, replace relay and go to step 14). - Check Voltage To Relay Coil
- Turn ignition switch to ON position. Measure voltage between ground and Light Blue/Pink wire at ABS main relay connector. If voltage is 10 volts or more, replace relay and check system operation. If voltage is less than 10 volts, repair open circuit in Light Blue/Pink wire. Go to next step. - Verify Repair
- Turn ignition switch to OFF position. Reconnect and reassemble all components. Clear all codes. Perform step 1) of DRIVE TEST under DIAGNOSIS & TESTING. Retrieve codes. If SYSTEM PASS is set, condition has been repaired and test is complete. If original code is set, repeat step 1). If a different code is set, go to appropriate trouble code test. See TROUBLE CODE DIRECTORY under TROUBLE CODE TESTS.