6–90
Copyright © 1998 General Motors Corp.
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
Main code 52 indicates a failed C3 pressure test. When a shift is commanded and C3 is the offgoing clutch, the
ECU expects the C3 pressure switch to open within a period of time after the shift is commanded. If the ECU does
not see the switch open, it assumes C3 has not released. If conditions for a shift exist, the shift is retried. If the
C3 pressure switch still remains closed, the code is logged and the DO NOT SHIFT response is commanded. If
the code is set during a direction change, neutral with no clutches is commanded, otherwise the transmission is
commanded to the previous range. Additional codes could be logged for other shifts where “X” indicates the range
from and “Y” indicates the range to.
NOTE:
C3 tests are turned off below a calibrated temperature of –32ºC (–25°F).
Active Indicator Clearing Procedure:
•
Power down
•
Manual
NOTE:
Before troubleshooting, read Pages 6–17 and 6–18 of Section 6–5. Also, check battery and ECU input
voltages.
NOTE:
Intermittent connections or lack of battery-direct power and ground connections may cause this and
other codes.
Main
Code
Subcode
Meaning
52
01
L–1 upshift
52
08
L–N1 shift
52
32
3–2 downshift
52
34
3–4 upshift
52
54
5–4 downshift
52
56
5–6 upshift
52
71
R–1 shift
52
72
R–2 shift
52
78
R–N1 shift
52
79
R–2 shift (R to NNC to 2)
52
99
N3–N2 shift
52
XY
X to Y shift
CODE 52 XX — OFFGOING C3 PRESSURE SWITCH TEST DURING SHIFT
