Troubleshooting › Driving and parking assistance systems › Diagnosis
U11AA87-故障诊断 · T00607349

 U11AA87 - TroubleshootingU11AA87-故障诊断

Fault code description故障码说明
DTC故障码(DTC)
Fault code description故障码描述
Possible cause of failure可能故障原因
U11AA87
There is a fault in communication with MRR (forward radar) and messages are lost.与MRR(前向雷达)通信存在故障，报文丢失
1. Communication abnormality of front radar node1.前雷达节点通讯异常
Troubleshooting steps故障诊断步骤
①General inspection一般检查
1. Power state is "OFF", disconnect the negative terminal of the 12V battery.电源状态“OFF”，断开蓄电池负极。
2. Check whether the private CAN communication harness is damaged or broken.检查私有CAN通讯线束是否存在损坏、破裂等现象。
3. Check the private CAN communication harness connector for loose connections or damage.检查私有CAN通讯线束接插件是否存在虚接、损坏等现象。
Are the test results normal?检查结果是否正常？
Yes是 Go to step 2.去步骤2。
No否 Repair or replace faulty wiring harness or connector.维修或更换故障线束或接插件。
②Check forward radar检查前向雷达
1. Power status "OFF".电源状态“OFF”。
2. Connect the diagnostic tool.连接诊断仪。
3. Power status "ON".电源状态“ON”。
4. Use the diagnostic tool to check whether the forward radar is normal.使用诊断仪检查前向雷达是否正常。
Are the test results normal?检查结果是否正常？
Yes是 Go to step 3.去步骤3。
No否 Overhaul forward radar.检修前向雷达。
③Check the private CAN communication harness between the forward radar and the lane departure warning ECU检查前向雷达与车道偏离预警ECU之间的私有CAN通讯线束
Graphic
1. Power status is "OFF", disconnect the negative terminal of the 12V battery.电源状态“OFF”,断开蓄电池负极。
2. Disconnect the forward radar harness connector FP12 and the lane departure warning ECU harness connector BD36.断开前向雷达线束接插件FP12和车道偏离预警ECU线束接插件BD36。
3. Use a multimeter to measure the resistance between pins 2/3 of FP12 and pins 10/11 of BD36.使用万用表测量FP12的2/3号针脚和BD36的10/11号针脚之间的电阻。
Standard resistance value: <1标准电阻值：<1 Ω
Are the test results normal?检查结果是否正常？
Yes是 Go to step 4.去步骤4。
No否 Repair or replace the faulty wiring harness.维修或更换故障线束。
④Replace lane departure warning ECU更换车道偏离预警ECU
1. Replace with a new lane departure warning ECU and check whether the fault code and symptoms are eliminated.更换新的车道偏离预警ECU，检查故障码及症状是否排除。
Are the test results normal?检查结果是否正常？
Yes是 Fault resolved.故障排除。
No否 Look for causes from other symptoms.从其他症状查找原因。
  Caution:注意：
♦  After replacing the lane departure warning ECU, you need to use a diagnostic tool to recalibrate the lane departure warning ECU.更换车道偏离预警ECU后，需用诊断仪对车道偏离预警ECU重新标定。