I have an older, lower hour (3100 hrs) 928G that won’t shift into reverse. Serial 4TF57981. Shifting problem was intermittent, now all the time. I believe the machine is too old to display codes (I may be wrong). Wanted to rule out mechanical or solenoid problem, so I switched plugs for Reverse solenoid and Fwd Low and machine will now shift into reverse when put into forward but now no forward in reverse. Thought problem may be in shifter, so I depinned connector in dash and switched the 755 and 750 wire. With shifter wires swapped, it would shift into forward when shifter in reverse but would not shift into reverse when shifted forward. I believe there is a problem in the wiring between the shift lever and solenoid valve. I have wiring diagram for shift lever, but nothing beyond that. Can anyone help with wiring diagram from shift lever to solenoid. Also would like to back probe and meter at various connectors, but not sure what to look for. Any assistance is greatly appreciated. Thanks
FYI serial number you provided is for the engine. See attached for machine information. Me or someone else will be along with more info shortly.
Sorry, how about 6XR02060
Keep an eye on your messages. An electrical schematic will be forthcoming shortly.
You can actually pull Codes on it. A bit old school by today's standards. You pull the Harness Code Plug and watch the Diagnostic indicator for Blink Codes but it still ought to work. See attachment. It has the procedure of how to extract them, and a list of Codes. Post back if you need more guidance or with a list of Codes.
Wanted to give a big Thank You for all the help. With the provided schematics, I was able to identify the Autoshift Control as a great place to start checking for continuity as the wires from the shifter and the shift solenoids all terminate there. The schematic gave a misleading component location (it shows the engine compartment?), but I was able to locate the module by the wire ID numbers. When I removed the module, a broken grey wire was immediately noticeable that was hidden by the harness when the module was installed. The wire was marked 755 and after consulting the schematic, I confirmed this was the output from the shifter to the module for Reverse. I repaired the wire and reinstalled the module. I’m happy to report all functions have been restored. Thanks again for all the help!