I'm having a problem with my 2008 caterpillar 279C. The Driver alert light is flashing. It will operate the hydraulics for the bucket and arms but it will not operate the machines tracks because the parking switch will not turn off to move the machine. The wiring harness for the drive sensors are good. I don't know how to see what code it had on the display. Any help would be great. Thanks
Hey mate I'm going through this very issue. First to find the error code you will have to get access to a cat ET machine your local service can help you there. My issue was a bad alternator causing low voltage to the inputs causing them to not work. This low voltage effected everything from the door switch to the arm sensors so that could be your issue. Just check your arm rest sensor and your door sensors to see if they are ok. Hope I helped you out a little. Sent from my SM-N910G using Tapatalk
do you have the optional cab display on the right hand side Mark
Livetoride I will check the safety switches tomorrow but I believe I can see them going off on the display when they are on. I'll check the alternator for voltage then also.
Yeah its just a thought if the hand brake isn't coming off I believe it could be one of those sensors being faulty. The right hand side of my alternator output was stuffed that what was causing my faults
Mark 250 yes I do have the display on the right side.
ok, to enable service mode hold the scroll up button and the select button at the same time for 3 seconds once in service mode you can scroll trough 4 modes mode 1 is for active diagnostics mode 2 is for logged diagnostics mode 3 is for active events mode 4 is for logged events record all numbers and post back Mark
Mode 1 - 77 Mode 2 - 78 Mode 3 - 0 Mode 4 - 0
hi, you are not in the correct mode, at a guess you are in service mode 5 and the numbers will be engine coolant temp and hydraulic oil temp there are 7 or 8 modes. you want the diagnostic service mode and will look something like this this diagnostic code consists of 3 components 1/ MID which is the module identifier in this case 039 (ECM which concerns the fault) 2/ CID which is the component identifier usually 4 digits (actual component or circuit at fault) 3/ FMI which is failure mode identifier usually 2 digits (the way the component or circuit failed ) as you scroll through the main screens with the select button, one of the screens will show the 039 number this will then change to a 6 digit number which is the CID and the FMI combined these numbers help us track down your problem Mark
here is a break down of the 7 service modes
I don't have a 039 number anywhere. The only other numbers I can seem to find are 2474 - 3 2476 - 3 1251 - 4 None of the service modes say what they are as far I understand.
those are the numbers we need if the fault is active the word" serv code" will be displayed with the code 1251-04 indicates that the alternator R terminal output is incorrect and that the R terminal voltage is low (this is a very specific output from the r terminal and some non OEM replacement alternators cant provide this signal) with a digital meter the output should be between 11 to 32 volt square wave and between 0 and 2 kHz for a quick and nasty check use voltage setting and vary rpm ,voltage should change with rpm also check your green wire resistance between the alternator and the disconnected harness plug at the ECM 2474-03 and 2476 -03 are in relation to the LH joystick signals being above normal because the 2 codes are common with in the joy stick I would check that you have 12v at terminal 1 on the 6 pin connector at base of joystick .I would also check that you have a good solid ground for pin no 2 on the 6 pin connector at base of joy stick. fuse no A4 supply's power to the base of the joystick Mark 2474-03
Mark a question for you. Is the R terminal an output from the alternator or is it somewhere else? I'm getting no voltage at all from the R output but upon inspection of the plug that goes into the back alternator I only have a plug with 2 wires and we can't figure out the issue.
the R terminal is on the alternator. try using your meter on AC volts as it is taken off the stator wires directly before the rectifier