DDEC TROUBLESHOOTING
[c] If code 41 is displayed, refer to section 41.3.1.
[d] If code 42 is displayed, refer to section 42.3.1.
10.2.5
Check Timing Reference Sensor
Perform the following steps to check the TRS:
1. Turn vehicle ignition OFF.
2. Disconnect engine harness connector at the ECM.
3. Measure resistance between sockets T1 and T2 at the engine harness connector.
[a] If the resistance measurement is greater than 200 , refer to section 41.3.3.
[b] If the resistance measurement is less than 100 , refer to section 41.3.2.
[c] If the resistance measurement is between 100 and 200 , refer to section 10.2.6.
10.2.6
Check Synchronous Reference Sensor / Timing Reference Sensor
Mounting
Perform the following steps to check the SRS/TRS mounting and the bracket:
1. Inspect SRS/TRS mounting.
[a] If the sensor and mount are secure, refer to section 10.2.7.
[b] If the sensor and mount are not secure, tighten the bolt or replace if necessary.
Refer to section 10.2.27.
10.2.7
Check Pulse Wheel
Perform the following steps to check the pulse wheel:
1. Inspect DDEC® pulse wheel for loose wheel or chipped or missing teeth.
[a] If the pulse wheel is damaged, repair or replace as necessary. Refer to section 10.2.27.
[b] If the pulse wheel is not damaged, refer to section 10.2.8.
10.2.8
Check ECM Connectors
Perform the following steps to check the ECM connectors:
1. Turn vehicle ignition OFF.
2. Disconnect all connectors at the ECM.
3. Check terminals at all ECM connectors (both the ECM and harness side) for damaged,
bent, corroded or unseated pins or sockets.
[a] If the terminals and connectors are damaged, repair them. Refer to section 10.2.27.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
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