DDEC Diagnostic Codes
The DDEC V system allows for an increased processor speed and increased memory.
Note: Due to the nature of the DDEC V System always start your diagnosis by refering to section "18.3 First Step for Diagnosing a Fault Within the DDEC System" , “First Step for Diagnosing a Fault Within the DDEC System.”
A diagnostic code indicates a problem in a given circuit (i.e. diagnostic Flash Code 14 indicates a problem in the oil or coolant temperature sensor circuit). This includes the oil or coolant temperature sensor, connector, harness, and Electronic Control Unit (ECM/ECU). The procedure for finding the problem can be found in Flash Code 14, refer to "24.2 Troubleshooting Flash Code 14, PID 110/FMI 3" . Similar sections are provided for each code. Remember, diagnosis should always begin at the start of the section. An oil or coolant temperature sensor problem will quickly lead you to section 14, but first verify the code or symptom.
Since the self-diagnostics do not detect all possible faults, the absence of a code does not mean there are not problems in the system. If a DDEC problem is suspected, even in the absence of a code, refer to "18.3 First Step for Diagnosing a Fault Within the DDEC System" , anyway. This section can lead you to other sections that can aid in the troubleshooting process - where DDEC problems may occur, but do not generate a code.
The identifiers used by DDEC are defined and listed in Table "Identifiers Used by DDEC" .
Failure Mode Identifier (FMI)
The FMI describes the type of failure detected in the subsystem and identified by the PID and SID.
Message Identification Character (MID)
THE MID is the first byte or character of each message that identifies which microcomputer on DDEC J1587 serial communication link originated the information.
Parameter Identification Character (PID)
A PID is a single byte character used in DDEC J1587 messages to identify the data byte(s) that follow. PIDs identify the parameters transmitted.
Subsystem Identification Character (SID)
A SID is a single byte character used to identify field-repairable or replaceable subsystems for which failures can be detected or isolated.
A Bulb and System Check
As a bulb and system check, the Check Engine Light/Amber Warning Lamp (CEL/AWL) and the Stop Engine Light/Red Stop Lamp (SEL/RSL) will come on for five seconds when the ignition switch is first turned on. If the unit is programmed for the Cruise Control feature, the Cruise Active Light (if equipped) will also turn on for five seconds.
If the CEL/AWL comes on during vehicle operation, it indicates the self diagnostic system has detected a fault.
When the Diagnostic Request Switch is held, the diagnostic system will flash the yellow or red light located on the dash of the vehicle. The light will be flashing the code(s) indicating the problem areas. If the SEL/RSL comes on during vehicle operation, it indicates the DDEC System has detected a potential engine damaging condition. The engine should be shut down immediately and checked for the problem.
Active codes will be flashed on the SEL/RSL in numerical flash code order. If there are no active codes, a code 25 will be flashed.
Inactive codes will be flashed on the CEL/AWL in most recent to least recent order. If there are no inactive codes, a code 25 will be flashed.
Active codes are conditions that are presently occurring and causing the CEL/AWL to be illuminated. All current active codes will be displayed for the entire system, including single, dual and triple ECM/ECU applications. The display for each code is as follows:
Line 1: ## MID: XXX XXXXXXXX
Line 2: PID Description
Line 3: FMI Description
Line 4: ↑ A## PID: XXX FMI: XX ↓
##: Indicates the DDC diagnostic flash code number
MID: Message Identification Character
PID: Parameter Identification Character
FMI: Failure Mode Identifier
A##: Numerical count of active codes
↑↓: Indicates additional codes are stored in ECM/ECU memory
Inactive codes are faults that have occurred previously. All current inactive codes will be displayed for the entire system, including single, dual, and triple ECM/ECU applications. The display for each code is as follows:
SCREEN #1; SCREEN #2
Line 1: ## MID: XXX XXXXXX XX ; Line 5: 1st: Last:
Line 2: PID Description; Line 6: Total#:
Line 3: FMI Description; Line 7: Total Time:
Line 4: ↑ |## PID: XXX FMI: XX ↓; Line 8: Min/Max:
##: Indicates the DDC diagnostic flash code number
|##: Numerical Count of inactive codes
1st: First occurrence of the diagnostic code in engine hours
Last: Last occurrence of the diagnostic code in engine hours
Total#: Total number of occurrences
Total Time: Total engine seconds that the diagnostic code was active
Min/Max: Minimum/Maximum value recorded during diagnostic condition
This feature allows diagnostic codes stored in the ECM/ECUs to be erased. An audit trail of when the codes were last erased will be displayed in engine hours.
Engine Hours of Last Clear Codes: XXXX
Message Identification Descriptions
MID: 128 ENGINE refers to single ECM/ECU applications
Diagnostic codes with Subsystem Identification Characters (SIDs) that reference Auxiliary Outputs # 1-8 (SIDs: 26, 40, 51, 52, 53, 54, 55, 56) will look up the parameter text description in a table to identify the function assigned to the auxiliary output channel.
Diagnostic codes with SIDs that reference PWM Outputs #1 through #4 (SIDs: 57, 58, 59 & 60) will look up the parameter text description in a table to identify the function assigned to the PWM output channel.
Injector Response Time Codes Long and Injector Response Time Codes Short will use a table of injector numbering to identify the appropriate engine cylinder number.
|Series 60 DDEC V Troubleshooting Guide - 6SE570|
|Generated on 10-13-2008|