DDEC TROUBLESHOOTING
[b] If the terminals and connectors are not damaged, replace the FPS and
refer to section 37.3.9.
37.3.5
Check for Short
Perform the following steps to check for a short.
1. Turn ignition OFF.
2. Disconnect the engine harness connectors at the ECM.
3. Measure resistance between sockets W1 and M1 on the engine harness connector.
[a] If the resistance measurement is greater than 100
or open, refer to section 37.3.6.
[b] If the resistance measurement is less than or equal to 100 , the signal line (#905) is
shorted to the engine +5 volt line (#416). Repair the short and refer to section 37.3.9.
37.3.6
Check for Short to Battery +
Perform the following steps to check for a short to battery.
1. Remove both fuses to the ECM.
2. Disconnect the vehicle harness and 5-way power connectors at the ECM. See Figure 37-3.
3. Measure resistance between socket M1 on the engine harness connector and socket B3
of the vehicle harness connector, and between M1 and the 5-way power harness sockets
A and C.
[a] If the resistance measurement is greater than 1,000
or open, refer to section 37.3.8.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
37-7
