HOUSING GP-ENGINE BRAKE 1895949 - Caterpillar

The purpose of this section is to aid the operator in solving common problems with the M5X communication protocol. This section should only be used for the M5X programming troubleshooting.
Table 1
M5X COMMUNICATION TROUBLESHOOTING    
Problem    Possible Explanation    Action Required    
CCM shows error codes E02 and E08 when receiving data from the PC and will not communicate.     1. There is a protocol error.
2. The data is not in ASCII format.
3. An incorrect checksum was sent.
4. Baud rate of the CCM and PC not matched.     Correct the message being sent to the CCM    
RS-232 receive lights are not lighted, and the CCM will not communicate with the PC even though no error codes are appearing.     Hardware connection between the PC and CCM is corrupted or disconnected.     Using the CCM PC software, connect to the CCM and determine if the connection to the PC is valid.    
Cannot log into the CCM     Connection problem exists or using the wrong M5X protocol for logging in.     Use a read request (PID $F0 $12) to verify that the PC is available to communicate with the CCM. If a valid response is returned, proceed to log in as described in the Logging in section of this manual. If the password has been forgotten, call the CCM Help Desk.    
Cannot get data from the electronic controller.     1. The electronic controller specified is not available.
2. The logged in security level is not high enough to support the request.
3. The electronic controller does not support the PID.     1. Verify that the electronic controller and the CCM are connected on the same data link.
2. Verify that the logged in security level is high enough to support the request.
3. Verify that the electronic controller supports the PID being requested.    
Multiple responses are being generated from a single electronic controller     Multiple electronic controllers have the same MID.     Program the engine number of the electronic controller. Refer to the CCM/Data Link Guidelines section and Programming the Engine Number section in this manual.    
An entire broadcast list is not returned.     1. The electronic controller specified is not available.
2. The electronic controller does not support any one of the PID's.
3. The PID contains greater than two bytes of data.     Refer to the CCM Customized System section, IID 10 and IID 13 in this manual    
A broadcast list update rate is too slow or inconsistent.     1. Too many parameters are being requested.
2. RS-232 baud rate is slow.     1. Verify that the RS-232 and modem baud rates are at least 9600 baud. CCM can not broadcast more than 40 parameters per second. Use IID 13, Byte 7 to slow the update rate for stable parameters such as hour meter, atmospheric pressure, temperature, diagnostics, etc. Use a faster rate for more dynamic parameters such as engine speed, oil pressure, etc. Refer to the RS-232 Communication Protocol for Customized Systems section in this manual for