DDEC TROUBLESHOOTING
[b] If the voltage measurement is less than 11.5 volts, the ECM ground wire (ck#150) is
open or has a poor connection. Repair open; refer to section 10.2.27.
Figure 10-5
5-Way ECM Power Harness Connector
10.2.20 Check Ignition Fuse
Perform the following steps to check the ignition fuse:
1. Turn ignition OFF.
2. Check 5-amp ignition fuse or circuit breaker.
[a] If both the fuse and circuit breaker are okay, refer to section 10.2.21.
[b] If the fuse or circuit breaker are not okay, refer to section 10.2.22.
10.2.21 Check for Open
Perform the following steps to check if the ignition wire is open:
1. Measure voltage between battery side (hot side) of the 5-amp ignition fuse (red lead)
and a good ground (black lead).
[a] If the voltage measurement is less than 11.5 volts, refer to section 10.2.24.
[b] If the voltage measurement is greater than or equal to 11.5 volts, the ignition line
(circuit #439) is open. Repair the open; refer to section 10.2.27.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
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