Diagnostic Tool
The diagnostic tool for Detroit Diesel Electronic Control (DDEC 10 and newer) is the DiagnosticLink® 8.x. DiagnosticLink requirements are listed earlier in the manual under Data Recording Capability.
Once the malfunction has been corrected, the DDEC system will return the engine to normal operation.
The air temperature in the intake system is increased with the addition of EGR. DDEC is programmed to reduce fueling (power) for a short time to reduce air and coolant temperatures when necessary.
DDEC will store an information code when this event occurs, but no corrective action is required. This action is designed to maintain operation without a noticeable effect on vehicle performance.
Flashing Malfunction Codes
All malfunction codes are four digits. The malfunction code recorded in the computer memory will remain until it is erased by a technician.
The flashing malfunction code can also be obtained by the operator. To support flashing codes, a Stop Engine Override/Diagnostic Request Switch must be configured and the AWL (Check Engine) and RSL (Stop Engine) must be hard-wired. The CPC cannot flash these lamps if they are not hard-wired.
The flashing code feature may be activated by satisfying one of the following conditions:
- Engine speed is less than 100 rpm and the Stop Engine Override Switch is put in the ON position.
- Idle Governor is active and the Stop Engine Override Switch is put in the ON position.
- Vehicle speed is less than three mph. Parking Brake is activated and the Stop Engine Override Switch is put in the ON position.
The flashing code feature is deactivated once the Stop Engine Override Switch is returned to the OFF position or the listed conditions are no longer satisfied.
Only one light will be flashing codes at any time. All codes will be flashed twice. The inter-digit pause is 1.5 seconds. The pause between codes is 3.5 seconds. The same 3.5-second pause occurs as the switch is made from RSL (Stop Engine) to AWL (Check Engine).
When code flashing is initiated, the active codes will be flashed on the RSL (Stop Engine). Then the inactive codes will be flashed on the AWL (Check Engine). When all the inactive codes have been flashed, the process of flashing all the active codes followed by all the inactive codes will repeat until the conditions for code flashing are no longer satisfied.
If there are no active or inactive faults, the number 3 is flashed once followed by a gap of three seconds.
Reading Fault Codes
To read the fault codes, press and hold the Stop Engine Override / Diagnostic Request Switch.
Active codes will be flashed on the RSL (Stop Engine) first, followed by inactive codes being flashed on the AWL (Check Engine). The codes will continue to flash and repeat as long as the Diagnostic Request Switch is held in the ON position. Both CPC and MCM faults are included.
Active Codes
The active codes will be flashed on the RSL (Stop Engine) in the order of most recent to least recent occurrence based on engine hours.
Inactive Codes
The inactive codes will be flashed on the AWL (Check Engine) in the order of most recent to least recent occurrence based on engine hours.