Hi team, I need your strong advice. I have an CAT M317 wheeled excavator equipped with C4.4 ACERT engine. I’m encountering a problem which involves engine speed sensor. As I linked up CAT ET service tooling, status flag posted “ no engine speed”. As I crank the engine and monitor “no start parameter”, Injector disabled is “ on ” during cranking resulting to no fuel injection into the combustion chamber. I tried disconnecting the primary engine speed sensor, fuel injection occurs and engine starts. How does it happen? As per my observation within the no start parameter during cranking, primary and secondary engine speed sensor was detected. Given the fact that the sensors are newly replaced. Kindly help me within this matter. Thankyou!
I think it might be because the two speed sensors are giving different signals to the ecm. The ecm won’t inject fuel if the signals don’t match. Seems like the primary sensor could be faulty. Can you put the old sensor back in ?
Hi Sir, I already tried putting the old primary speed sensor back and it’s still the same scenario. Actually I have an identical unit which is running normally, I also tried borrowing the sensor from the running unit and transferred to the down unit, but still the error exist.
Please post a machine Serial Number and any Diagnostic Codes regarding the Primary Speed Sensor that may be showing on ET. You will likely be requiring the electrical schematic for the machine. If you have replaced the Primary SS with one from another machine that runs fine and the fault is still there it points possibly to an electrical wiring problem.
I used to look after a Prinoth Trooper with a 4.4 Acert. It developed a very similar problem just off warranty with very low hours. The reluctor ring that is attached to the crankshaft had the screws come loose. After the screws failed it refused to run. Showed no engine speed when cranking on the J-Pro software.
Got it! I will check the reluctor ring. I dont expect that it is possible to happen. Well the unit service hours already 7000hrs. Now I assumed that the primary engine SS/proximity sensor read incorrect data. Hence, turns per cycle reading was invalid. Thankyou!