Important: The following steps must be completed before using the symptom tables.
- Perform the 
Diagnostic System Check - Power Take-Off (PTO) 
 before using the Symptom  Tables in order
 to verify  that all of  the following are true:
 
| •  | There are no PCM or TAC module DTCs set. | 
 
| •  | The PCM and TAC module can communicate to each other via the serial
  data links. | 
 
- Review the system operation in order to familiarize yourself with
   the system functions. Refer to 
Power Take-Off (PTO) Description and Operation 
.
 
Visual/Physical Inspection
|     •  | Inspect the easily accessible, or the visible system components
   for obvious damage or conditions which could cause the symptom. | 
 
|     •  | Inspect the transmission and the hydraulic pump for the proper
  fluid level. | 
 
Intermittent
Faulty electrical connections or wiring may be the cause of intermittent
   conditions. Refer to 
Testing for Intermittent Conditions and Poor Connections 
 in  Wiring Systems.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order
   to diagnose the symptom: