DDEC TROUBLESHOOTING
1. Turn ignition OFF.
2. Disconnect the vehicle harness connector at the ECM.
3. Ensure the clutch is not engaged.
4. Measure resistance between the clutch cavity (i.e. J2) on the vehicle harness connector
and a good ground.
[a] If the resistance measurement is greater than 5 , or open, the clutch switch is
miswired or faulty, circuit #953 is open, or there is a bad battery ground. Rewire,
repair the short or replace the switch. Refer to section 10.7.16.
[b] If the resistance measurement is less than or equal to 5 , refer to section 10.7.2.
10.7.10 Check for Short at the Clutch Service/Circuit
Perform the following steps to check for a short:
1. Turn ignition OFF.
2. Disconnect the vehicle harness connector at the ECM.
3. Engage the clutch.
4. Measure resistance between the clutch cavity (i.e. J2) on the vehicle harness connector
and a good ground.
[a] If the resistance measurement is less than or equal to 100 , the clutch switch is
miswired or faulty, or the clutch circuit is shorted to ground. Rewire, repair the short
or replace the switch. Refer to section 10.7.16.
[b] If the resistance measurement is greater than 100 , or open, refer to section 10.7.2.
10.7.11 Check for Short at the Set/Coast Circuit
Perform the following steps to check for a short:
1. Turn ignition OFF.
2. Disconnect the vehicle harness connector at the ECM.
3. Measure resistance between the set/coast cavity (i.e. J2) and a good ground.
[a] If the resistance measurement is less than or equal to 100 , the set/coast switch is
shorted, or a short to ground exists in the set/coast circuit (i.e. #541). Repair the short
or replace the switch. Refer to section 10.7.16.
[b] If the resistance measurement is greater than 100 , refer to section 10.7.2.
10.7.12 Check for Open at the Set/Coast Circuit
Perform the following steps to check for an open:
1. Turn ignition OFF.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
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