Grader cat0140HEXZH00386. When moving forward, there is only one speed of 1. Image 1-2. If you move the lever very quickly from position N or Parking to position -2 to 8, the gear turns on. Image 3-4. To change the speed, you need to switch to the N position again very quickly and select the speed. There are no errors in CAT ET.
If, as you say, there are no diagnostic codes, then look at this. Troubleshooting Without An ECAP Or ECM Diagnostics Problem: "First Gear Out Of Neutral" Only Working Gear Corrective Procedure: 1. Start engine and operate the machine in order to determine which gears are operable. 2. Stop the machine, engage the parking brake and turn off the engine. 3. Jumper the manual modulation pressure switch in order to determine if this pressure switch is working. The manual modulation pressure switch is located on the Hydraulic Clutch Modulation Control (HCM). Disconnect the 2 pin connector and jumper Pins 1 and 2 of the receptacle. 4. Start the machine and attempt to operate the machine in all gears. If the machine has more than one gear out of neutral then the manual modulation pressure switch has failed. If the first gear out of neutral is still the only gear available, proceed to Step 5. 5. From Step 4, the wiring harness between the manual modulation pressure switch and the transmission ECM is suspect. Remove the transmission ECM from under the cab and disconnect both 40 pin Deutch® connectors. Check continuity between Pins J1-2 and J2-11 of the machine harness. If continuity is obtained while the jumper is in place, the transmission ECM has failed. If continuity is not obtained, the wiring harness between the transmission ECM and the manual modulation pressure switch has failed.
If you need a wiring diagram, write
Thank you. The electrical wiring has been checked. It's working fine. The HCM has a resistance of 10kOm if the pedal is not pressed and changes the resistance to 800 ohms if pressed. The ECM was installed from a serviceable grader. There are no changes. P.S. I installed the jumper 2-11.There are no changes.
Can you give some information regarding how this problem developed. Did it slowly get worse over time or did it appear literally from one day to the next.? For your information there was a change in part number of the ECM. To install the newer Part Number of ECM required changes to the machine wiring.
The operator said he turned off the car for the night. The problem appeared in the morning
My first thought would be the Direction and Speed Control Switch that is mounted directly under the transmission shift lever. Do you have another machine available that you could remove one for a test.?
The direction and speed switch is checked. All signals are coming to the ECM correctly.
May I ask how the signals were checked.? If you had an ECM available from another working machine to use for a test then why not borrow the speed control switch from the same machine, just to rule it out as a possibility.?
What version of the transmission flash file is currently installed? And if you installed an ECM from another maschine, have you tried installing the suspect ECM on that maschine?
This……..
I removed and disassembled the speed and direction switch. I checked the operation of the contacts.
The feedback signals for the ECM are the secondary shaft speed sensor and the pressure modulator. Which signal prevents the ECM from switching speeds?
I agree with @Deimos - to prove both the ECM and the direction control switch are good the best way to do that would be install them separately on another machine. If both prove good the diagnostics continue on the wiring harnesses, etc, of machine XZH000386.
The problem is solved. The reason is the connector contact. When checking the wires, the contact was present and did not arouse suspicion. When connecting the pressure sensor connector or jumper, the contact disappeared. Breakage inside the connector housing. Replaced the connector. Deimos, огромное спасибо!!!! Данная процедура с перемычкой напрямую заставляет ЭБУ подключать передачи. Очень полезно!!!
Excellent news. Which connector was the problem.?