DDEC TROUBLESHOOTING
9.1
FIRST STEP FOR DIAGNOSING A FAULT WITHIN THE DDEC SYSTEM
The following procedure is the starting point for diagnosing DDEC codes using the Diagnostic
Data Reader (DDR).
9.1.1
Check Engine Light
Perform the following steps to check the Check Engine Light (CEL):
1. Turn the ignition on while at the same time observing the Check/Stop Engine light (engine
not running).
[a] If the CEL comes on and stays on, refer to section 9.1.2.
[b] If the CEL comes on for up to five seconds, and then turns off, refer to section 9.1.3.
[c] If the CEL does come on, but the condition of light is erratic or intermittent,
refer to section 10.4.
[d] If the CEL does not come on, refer to section 10.4.
9.1.2
Read Active Codes
Perform the following steps to read the active codes.
1. Turn ignition on. Plug DDR into DDL connector. See Figure 9-1.
Figure 9-1
Diagnostic Connector
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
9-3
