Allison B 300, Руководство по устранению неисправностей

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Copyright © 1998 General Motors Corp. 6–21
DIAGNOSTIC CODES
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
4. If power is correct but the diagnostic tool reading indicates incorrect voltage, closely inspect
terminals B2 and B11; make sure they are not corroded or deformed. Clean or replace as necessary
(see Appendix E, Paragraph 1–1).
5. If the voltage condition is intermittent, closely inspect the vehicle wiring for transmission system
power and grounds. Check for loose, dirty, or painted connections. Check the VIM for loose,
incorrect, or overheating relays or fuses (refer to Appendix G). Check for wires that are chafed and
touching other components.
6. If no other cause is found, 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.
Table 6–3. Voltage Chart
Voltage Condition
35.0
(High Set Point)
Maximum Surge For 2 Minutes, High Fail Limit
32.0 Maximum Continuous ECU Voltage
10.0
(Med. Low Set Point)
Cannot Compensate W/Sub-Modulation (Bad Shifts).
Adaptive logic stops functioning
8.0 Low Voltage Fail Limit, Set Code, DNS
7.0
(Low Set Point)
Software Off (ECU loses power)
4.5 Neutral Start Off
CODE 13 XX — ECU INPUT VOLTAGE
(Figure 6–2)