P144262 - TroubleshootingP144262-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
P144262	Brake switch signal does not match制动开关信号不匹配	1. The brake switch signal is abnormal1.制动开关信号异常

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 the brake light switch wiring harness for damage, breakage, etc.检查制动灯开关线束是否存在损坏、断裂等现象。 3. Check the brake light switch harness connector for loose connection or damage.检查制动灯开关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 brake switch harness or connector.维修或更换制动开关线束或接插件。
②Check brake lights检查制动灯
1. Power status "ON".电源状态“ON”。 2. Depress the brake pedal and check whether the brake light is normal.踩下制动踏板，检查制动灯是否正常。 Are the test results normal?检查结果是否正常？ Yes是 Go to step 6.去步骤6。 No否 Go to step 3.去步骤3。
③Check brake light switch supply voltage检查制动灯开关供电电压
	1. The vehicle is powered on.车辆上电。 2. Use a digital multimeter to measure the voltage between pin 2/3 of FB52 and ground.用数字万用表测量FB52的2/3号针脚与接地之间的电压。 Standard voltage value: about 14V标准电压值：约14V 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 Check the brake light switch power supply circuit.检修制动灯开关供电线路。
④Replace brake light switch更换制动灯开关
1. Replace the brake light switch with a new one and check whether the fault code and symptoms are eliminated.更换新的制动灯开关，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 5.去步骤5。
⑤Check the signal harness between the brake switch and the vehicle controller检查制动开关至整车控制器之间的信号线束
	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 brake light switch harness connector FB52 and the vehicle controller harness connector FB42.断开制动灯开关线束接插件FB52和整车控制器线束接插件FB42。 3. Use a digital multimeter to measure the resistance between pin 1/4 of FB52 and pin 19/35 of FB42.用数字万用表测量FB52的1/4号针脚与FB42的19/35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 6.去步骤6。 No否 Repair or replace the signal harness between the brake light switch and the vehicle controller.维修或更换制动灯开关至整车控制器之间的信号线束。
⑥Replace vehicle controller更换整车控制器
1. Replace the vehicle controller with a new one and check whether the fault code and symptoms are eliminated.更换新的整车控制器，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 vehicle controller, you need to use a diagnostic tool to recalibrate the vehicle controller.更换整车控制器后，需用诊断仪对整车控制器重新标定。