In the wheel loader section I have a thread on a older case 621 b that has lost all gears and the zf controller keeps shutting down I could really use some help on
Post up some schematics is my suggestion, as some can follow wires and offer some tests to confirm what should and should not be. Schematic showing Controller pwer in and out would be helpful. If you don't have schematics, I suggest you buy or find someone who does. Posting your serial number may help get a response. Simon C
Even in that old thread, the ZF mechanic wrote: first of all, look at the error codes, that's where you start, it's better if someone gives you advice, I make truck cranes and if someone gives me an error code, it's better
It’s an old enough machine it requires breakout boxes there is no on board diagnostics that I know off
You wrote that the speed sensor is good in terms of measurements, but what kind of impulses does it give, also what kind of engine speed do you have, it doesn't shift at higher speeds, there are many possibilities here... it could be that some relay doesn't send a strong enough signal, pedal position, turbine speed, really tough nut to crack
So looked at your schematic, you need to verify that you have clean power to the power showing as " Cab Switched Power" on the top of the schematic. There is a 5 amp fuse in the middle of the schematic. The Electronic Trans Control Module has Pins 1=2 that are Battery power. Bottom of the Module Pin #18+ 35 are both grounds. Fuse E is 3 Amps and needs to be checked. One of the other pictures you posted had a bunch of relays, one of which is Cab Power Relay. All of these things listed need to be checked back to battery positive or negative . I made myself up a set of leads to be able to rremove the relays and test them individually to find out if they can handle a load like 5-10 amps without dropping out. If they don't work when off , they definitely won't work when on the machine. Lots of things to test. Simon C