Replacement of the wiring harness is a very tedious task for us. I think most of the time, no one thinks about replacing the wiring harness. However, a car owner introduced by a friend on WeChat asked me that the 4S shop asked him to replace the entire floor harness of the car. So, should the wiring harness be replaced? Let's discuss it together.
The owner’s fault is described as follows: Cadillac ATs (2017 model)
Description of the problem: 1. During driving, the wrench was caught in the tires, the wiring harness was broken, and the car could not be started again; 2. After the plug-in was repaired and the plug-in was re-connected (fuel pump sensor), the car could be driven, but the fuel gauge was not on. Go, the engine fault light constant. 4S shops, it is recommended that car owners replace the entire wiring harness; non-4S shop repairers: only need to replace the oil pump sensor, no need to change the wiring harness.
Judging from the fault read by the diagnostic instrument, that is, the voltage of the fuel level sensor circuit is too high, and the fuel pump control module requests the fault indicator failure but does not request it. It can be preliminarily judged that the fuel pump sensor is damaged.
In combination with the picture of the fault description, the oil pump sensor is seriously damaged to the connector. It is reasonable to think that the oil pump sensor itself is damaged, a short circuit occurs, and the circuit voltage is too high. Of course, you should also check the line for damage to other parts, such as related insurance/connectors.
It is recommended to change the oil pump sensor first, and to directly replace the entire wiring harness is too much work, and it is terrible to think about the labor cost. Removing the wiring harness is basically equivalent to removing a car, which is likely to cause other problems. Personal opinion, unless the harness is seriously aging, damaged seriously, and the virtual connection/short-circuit part is not found, then consider replacing the harness.