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
5. If C3 is being held on hydraulically (C3 remains pressurized), drain the fluid, remove the control
module, disassemble and clean the control module, checking for damaged valve body gaskets or
stuck and sticky valves.
6. If the problem recurs, use a spare wire, if available, or provide a new wire (St. Clair P/N 200153
may be used for this purpose) for the C3 pressure switch in the external harness.
7. If the problem again recurs, replace the C solenoid.
8. 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 52 XX OFFGOING C3 PRESSURE SWITCH TEST DURING SHIFT