Hi, I have a request. I repaired a grader caterpillar 140H transmission electronic board and want to test it, If possible, guide me on how to simulate the gear shifter switch and the voltage applied to the pins of electronic board in different gears, also I want Arrangement of energizing the solenoid in different gears. Thanks,
Without the grader serial number, it is impossible to answer your question.
Serial number is 172-9389.
This is not the serial number of the 140H grader. The serial number should be on the plate. ECM 172-9389 is installed on many different machines. You need the serial number of your 140H machine to find the diagram.
172-9389 is the Part Number of the transmission ECM. As Dmitri says it requires the Serial Number of the machine on which that ECM is installed in order to supply information.
Should this information be enough? I think the gear shifter works analog. Look at the diagram for power contacts for each speed. But it seems to me that the easiest way to test the ECM is to install it on a grader.
Thank you very much for the information you sent me. For example, for the First forward, a negative signal is sent from the gear shifter to the pin the first and forward. is it correct?
Yes
The machine is too far away from me. Before installing the ecm, I want to test it. According to a video on YouTube, the inside of the shifter consists of switches and a selector that provides the digital signal.
If the gear selector were to transmit a digital signal, it would be connected to the ECM via the CAT DATA Link or CAN Data Link. But in the circuit, each selector contact is connected to its own ECM contact. Information from System Operation "The transmission control is located on the right side of the operator in the operator compartment. The transmission control is a mechanically moved lever which selects PARK, NEUTRAL, one to eight FORWARD, and one to six REVERSE speeds. The transmission control directs an electrical signal to the transmission ECM."
There are lots of things on YouTube - it doesn't make them true........ See the schematic posted by Dmitri above. The gear selection switch operates by grounding (via Pin 2) either one or two of the wires coming into it on Pins 1 and Pins 3-14. So for example if the switch is in the "Park" position Pin 13 is connected to Pin 2 through the switch contacts. All the other Pin contacts on the switch will be open circuit. When the ECM "sees" ground on Pin 13 it "knows" (from the internal software program loaded into it) that the switch is in the Park position. In a similar way if the switch was in 4th speed forward then Pins 6 (fourth speed) and 11 (Forward) would be connected to ground through the switch. Again those inputs to the ECM indicate the switch position.
Thank you for your complete explanation.
Hi guys, I tested ECM according to your guidance, then i installed on the machine and tested it in both cases ECM worked properly. After a few days, gears 5, 6, 7 and 8 forward and 5 and 6 backward do not work. Considering the arrangement of solenoid, could ECM be the problem?
Considering that you repaired the ECM yourself, such repairs usually do not last long. In any case, first you need to connect CAT ET and look at the speed switch parameters and the solenoids' activation status.