Machine: 2017 299D2 XHP Code: 2688-8 Right Drive Motors Speed sensor #2 abnormal frequency pulse width or period. What I have done: - swap speed sensors - Swap plugs under the cab. Both still give right side error code?? Suggestions?
Welcome to the Forums Lusk! Glad to have you. Nige would be the one to answer this question. He's become quite the expert on Cat CTL's. BTW - I moved this thread over from from the Backhoe Loader section. Best of luck.
I’ll post up the troubleshooting procedure but it will be tomorrow. You will probably need the electrical schematic and to identify the correct one will require the machine Serial Number.
Initially, I would just get an unexpected motor speed detection. You could let off the stick and it would go again and until you turn to certain way. When I swapped the two wires under the machine with the machine on now, I’m getting a constant right side, speed sensor fault and unexpected motor speed fault. Now it is constant is there a way to reset it? Suggestions
Not until the problem, whatever it is, is fixed. Attached the troubleshooting for 2688-08. Note carefully the comment about the machine having to be moved to register a "genuine" signal after repairs have been performed before the fault will disappear. Still waiting for a Serial Number to identify the correct electrical schematic.
I ran the machine for several minutes after I did each swap is there a timeframe on how long before it resets itself?
Not really a time frame, more a distance travelled. I would say off the top of my head that if the machine was to move maybe 50-100 yards that would probably be enough for the ECM to accept a signal as being genuine and change the 2688-8 Diagnostic Code from being Active to Logged.
Is there a way to do a reset? I was only receiving the code in Red until I switch the wires while the machine was running and now I am receiving the right side speed sensor code.
I had the same problem. I ended up replacing the deutsch connector on the outside where the speed sensor plugs in (on both sides). That was a few years ago. Hasn't happened since.
No - as I explained to you before the Code has to be fixed first then the machine operated for a certain distance to permit the "good" signal to cancel the Active Diagnostic Code. Have you performed the troubleshooting procedure yet.? What indications did that give you.? If you neeed a complete electrical schematic for your machine please ask.
I may try that. You replaced both ends of the short wiring harness that goes through the frame?
Yes. And some wires too. I did do some continuity testing from the sensor back to ECM.
And again he says …….. Carry out the troubleshooting procedure step by step. It will lead you to the cause of the problem. It might be an electronic system but it’s not rocket science. You don’t have to “try” anything.