DDEC TROUBLESHOOTING
10.2.17 Check Battery
Perform the following steps to check the battery:
1. Connect all connectors.
2. Turn ignition ON.
3. Measure voltage at battery (+) terminal (red lead) to the battery (-) terminal (black lead).
[a] If the voltage reading is less than 11.5 volts, service the discharged battery.
Refer to section 10.2.27.
[b] If the voltage reading is greater than or equal to 11.5 volts, an open or short to ground
exists in the battery (+) line. Repair the open. Refer to section 10.2.27.
10.2.18 Check Volts at Ignition Wire
Perform the following steps to check for +12 or +24 volts at the ignition wire:
1. Turn ignition OFF.
2. Disconnect the vehicle harness connector at the ECM. For vehicle harness schematic,
see Figure 10-4.
3. Turn ignition ON.
4. Measure voltage between socket B3 on the vehicle harness connector (red lead) and a
good ground (black lead).
[a] If the voltage measurement is greater than or equal to 11.5 volts,
refer to section 10.2.19.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
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