242B /BNX2856_ I need wiring schematic for reverse alarm and auxiliary function. The alarm itself works with power probe, checked the reverse pressure switch with air pressure and voltmeter. No voltage to pressure switch, I don't see any modules except engine ecu, and no fuses for vcu or tcu type module. These controls seem to be analog. Also checked and replaced 10 amp fuse for reverse alarm , original fuse did not appear to be blown just put a new one in anyway. There are some relays on left side engine compartment that the harness to reverse alarm seems to originated from. However, I can not see any brown wire coming from any of the relays that are brown as the one is to the alarm. The other is black to alarm , ground i assume. Have not even got into the auxiliary function at this time. Thanks
Don't know if this helps, or not, but I'm in a sarcastic mood... https://goo.gl/images/grFqhz
I like sarcasm! Cats not so much .
That S/N brings up a D7R.....still digging
BXM2856 by chance....?
Probably so, can't check for sure until tomorrow. 242B
PM me an email address and I’ll send the full interactive schematic.
http://www.catsch.info/RENR2863.html
I was able to run down the reverse alarm issue today. It was an anolog circuit with wire open in front harness. The auxiliary circuit runs through a module, so I am dealing with the roller switch on the right hand joystick. The voltage supply to the switch from module is about 7 volts . The rocker switch varies the voltage equally both directions. Four wires to and from the switch. supply voltage, module signal wire . calibration ( blanked out in plug) and return to module. The return wire is continent to frame ground , not sure it should be??? Thanks
Check and clean all of the fuses, my brother had all sorts of problems with a 277 which turned out to be a corroded fuse. Low voltage to the left joy stick when they hooked it up to Cats expensive computer ($750) . Use some dielectric grease when putting them back in. Steve
Based on an assumed Serial Number of BXM2856, here is a pdf schematic
Sorry for not following up with confirmation of serial number. It is BXM2856. I have not had a chance to dig any deeper into the auxillary function. But upon further thought, I think the return wire should be continent to frame ground when the harness is connected to module. If it is continent to frame when the connection to module is disconnected then that is an issue.
From past postings in this forum all these machines seem to be affected by moisture and dirt getting into electrical connections, especially under the cab floor where most of the electronics live. The file below combined with the electrical schematic may give you a better clue where to start looking. It won't be easy because there will be a lot of panels to remove before you can get to where you need to be.