Allison B 300, Руководство по устранению неисправностей

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Copyright © 1998 General Motors Corp. 6–81
W T E C I I E L E C T RO N I C C O N T RO L S T RO U B L E S H O OT I N G M A N UA L
Troubleshooting:
1. Check the transmission connector and make sure it is tightly connected. If the connector is
properly connected, disconnect the harness at the transmission and check for water contamination
and inspect the terminals in the external harness and feedthrough connectors. Clean or replace as
necessary (Appendix D).
2. If the connector is connected, clean, and not damaged, check the solenoid circuit in the
transmission for shorts to other wires. (Tool J 38850 may be useful in making this test.) Refer to
the system schematic and/or chart to identify wires in the internal harness which are connected. If
the short circuit is found, drain the fluid, remove the control module (refer to the transmission
Service Manual), and isolate the short. The short is probably in the feedthrough connector, internal
harness, or the solenoid itself (refer to Figure 6–1 for solenoid locations).
3. If the short is not found at the transmission connector, disconnect the connectors at the ECU and
inspect their terminals for damage or contamination. Clean or replace as necessary. If the terminals
are satisfactory, check the wires of the solenoid circuit in the external harness for shorts-to-ground
or shorts between wires. If a short is found in one of the wires, isolate and repair it or use a spare
wire in the external harness. Refer to Appendix E for connector/terminal repair information.
4. If the short is not found in either the transmission or the harness, the condition must be
intermittent.
5. Drain the fluid, remove the control module, and replace the solenoid and internal harness (refer to
the transmission Service Manual).
6. If the condition recurs, use spare wire(s) for the solenoid circuit indicated by the diagnostic code.
See Appendix D for location of spare wires and Appendix E for connector assembly/disassembly
information.
7. If the condition persists, replace the ECU. If replacing the ECU corrects the problem, reinstall the
original (bad) ECU to confirm that the problem is in the ECU. If the original ECU now works,
inspect the ECU connectors for any corrosion or damage which may cause an intermittent
condition. If the original problem recurs, reinstall the replacement ECU.
CODE 44 XX — SHORT-TO-GROUND IN SOLENOID CIRCUIT
(Figures 6–29, 6–30)