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
Main code 32 indicates the transmission gear ratio is correct, but the C3 pressure switch is open when it should be
When an ECU with a version 8 or 8A calibration is used with a pre-TransID transmission, 32 XX codes
are set because the ECU sees wire 195 is open. To correct this condition, convert to a TID 1 internal
harness or install Adapter P/N 200100 available from St. Clair Technologies.
Active Indicator Clearing Procedure:
Before troubleshooting, read Paragraph 56. Also, check battery and ECU input voltages.
1. Disconnect the transmission T harness connector at the ECU and the transmission. Check the
C3 switch circuit for opens, shorts to other wires, shorts-to-ground, or short-to-battery. If wiring
problems are found, isolate and repair. The C3 pressure switch closes at 206.8 ± 48 kPa (30±7psi);
resistance should be 2 Ohms maximum when the switch is closed and 20,000 to infinity when the
switch is open. Infinity is often indicated as OL (over limit) on a DVOM.
2. If problems are not found in the external harness, drain the fluid, remove the control module, and
check the internal harness for opens, shorts between wires, or shorts-to-ground (refer to the proper
transmission Service Manual). If wiring problems are found, isolate and repair.
3. If no wiring problems are found, replace the C3 pressure switch.
4. 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 circuit.
5. If the problem recurs again, replace the internal harness.
6. 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, in-
spect the ECU connectors for any corrosion or damage which may cause an intermittent condition.
If the original problem recurs, reinstall the replacement ECU.
C3 switch open in low range
(MD 3070 or HD 4070 only)
C3 switch open in third range
C3 switch open in fifth range
C3 switch open in reverse range
CODE 32 XX C3 PRESSURE SWITCH (Figure 510)