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What should I do if an electronically controlled diesel generator set cannot be started due to a wiring harness problem?

July 22, 2022
Generally speaking, the diesel engine electronic control system includes electronic control unit ECU, sensors, actuators and wiring harness, etc. The diesel engine electronic control system wiring harness is the carrier of power and various signals, and is the bridge between the control unit ECU and the engine for information exchange and control.
a. The vehicle and engine operating status signals collected by sensors, switches, etc., such as temperature, pressure, speed and other electrical signals to the ECU.
b. Transmit the control commands converted by ECU into control commands based on the judgment, analysis, calculation and processing of the input information to the actuator.
c. The battery electrical energy is supplied to the engine control system.
When there is a problem with the wiring harness, the diesel generator set may not start normally. For the problem that the diesel generator set cannot start due to the wiring harness problem, first confirm that the diesel generator set ECU has started to work, by using the key switch to power up the ECU, the diagnostic light and cold start light will flash down and then go out, indicating that the ECU is performing self-test and starting to work.
Diesel generator set starter relay is controlled by ECU
Check the data, check whether the relevant calibration amount is correct; in the case of determining the correct calibration value, check the neutral switch that is: gearcd-stn, if the value is 0, it indicates that it is not in neutral, you need to check whether the data is correct, after the data is correct, you can try to use the emergency start, if the starter by the action, then start to check the neutral wiring. In addition, you need to detect the signal of t50, t50cd-stdebval, if the starting process does not change to 1 then you need to check the wiring.
Diesel generator starter relay is not controlled by ECU
If the starter can act, but still can not start, first need to judge the synchronization signal engm-stsync, if the value in the starting process appears 48, it proves that the synchronization signal is correct, can not start the main reason is that the track pressure can not be established, low pressure oil circuit has air leakage, need to check whether the oil circuit to meet our requirements and oil circuit exhaust. If there is no 48 and a related synchronization error is reported, look for the crankshaft and camshaft signal sensors to find out the cause, such as: no machined hole in the flywheel or incorrect pairing phase relationship between the two. At this time, you can also unplug one of the sensors and try to start.
There are many reasons why a diesel generator set can not start, the starting system, electronically controlled fuel supply system, intake and exhaust system or diesel engine parts with clearance problems, may cause the unit can not start, this article for the wiring harness problem for you to put forward the corresponding solution, I hope it will help you.