W T E C I I I E L E C T R O N I C C O N T R O L S T R O U B L E S H O O T I N G M A N U A L
0011 00-118
CODE 66 XX — SCI (SERIAL COMMUNICATION INTERFACE) FAULT
Main code 69 indicates a problem which has been identified as being from within the ECU.
A “cateye” display or a blank display may occur with subcode 33.
A.
Active Indicator Clearing Procedure:
•
Power down
•
Manual — except subcodes 33, 35, 36, 41, 42, and 43
•
Self-clearing — subcode 42 and subcodes 33, 35, 36, and 41; after an ECU reset
NOTE:
Subcode 34 cannot be cleared.
B.
Troubleshooting:
1. For subcodes 27, 28, and 29, check for shorts to battery before replacing the ECU. Follow the
troubleshooting steps for code 42 XX for checking shorts to battery. If no shorts are 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 problem recurs, reinstall the new ECU to complete the repair.
2. For all other subcodes, replace the ECU.
Main
Code
Subcode
Meaning
69
27
ECU, Inoperative A-Hi switch
69
28
ECU, Inoperative F-Hi switch
69
29
ECU, Inoperative N-Hi and H-Hi switch
69
33
ECU, computer operating properly timeout
69
34
ECU, write timeout
69
35
ECU, checksum
69
36
ECU, RAM self-check failure
69
39
Communication chip addressing error
69
41
ECU, I/O ASIC addressing test
69
42
SPI output failure
69
43
SPI input failure
