B254700 - TroubleshootingB254700-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
B254700	Internal antenna 3 error内部天线3错误	1.Antenna connection problem1.天线连接问题

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 wiring harness of the detection antenna 3 in the car is damaged or broken.检查车内探测天线3线束是否存在损坏、断裂等现象。 3. Check whether there is any loose connection or damage to the 3rd harness connector of the detection antenna in the car.检查车内探测天线3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 the 3 wiring harness or connector of the vehicle detection antenna.维修或更换车内探测天线3线束或接插件。
②Check the signal wiring harness of vehicle interior detection antenna 3检查车内探测天线3信号线束
	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. Disconnect the in-vehicle detection antenna 3 harness connector BD82 and the integrated body control module harness connector BD57.断开车内探测天线3线束接插件BD82和集成式车身控制模块线束接插件BD57。 3. Use a digital multimeter to measure the resistance between pins 3/4 of BD82 and pins 39/52 of BD57.用数字万用表测量BD82的3/4号针脚与BD57的39/52号针脚之间的电阻。 Standard resistance value: <1标准电阻值：＜1Ω
	d. Use a digital multimeter to measure the resistance between pin 39/52 of BD57 and ground.d.用数字万用表测量BD57的39/52号针脚与接地之间的电阻。 Standard resistance value: >1M标准电阻值：＞1MΩ
	e. Connect the negative terminal of the 12V battery.e.连接蓄电池负极。 f. Use a digital multimeter to measure the voltage between pin 39/52 of BD57 and ground.f.用数字万用表测量BD57的39/52号针脚与接地之间的电压。 Standard voltage value: 0V标准电压值：0V 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 Repair or replace the signal wiring harness of the vehicle detection antenna 3.维修或更换车内探测天线3信号线束。
③Replace the interior detection antenna 3更换车内探测天线3
1. Replace the interior detection antenna 3 with a new one and check whether the fault code and symptoms are eliminated.更换新的车内探测天线3，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 Go to step 4.去步骤4。
④Replacing the integrated body control module更换集成式车身控制模块
1. Replace with a new integrated body control module and check whether the fault code and symptoms are eliminated.更换新的集成式车身控制模块，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 integrated body control module, you need to use a diagnostic tool to recalibrate the integrated body control module.更换集成式车身控制模块后，需用诊断仪对集成式车身控制模块重新标定。