1, 2 and 3 Digit Codes: 73

CODE NUMBER
Scan tool: 73
General scan tool: P1798

CODE NAME
Worn or burnt transmission fluid

CODE DESCRIPTION
With the A/C clutch engaged, convener clutch fully on, partial lock failure counter greater than equal to 20, and the turbine acceleration out of range.

THEORY OF OPERATION:
While in 3rd, 4th gear Fully electronically modulated converter clutch (FEMCC) and just before the A/C clutch engages, the PCM requests the TCM to momentarily establish partial electronically modulated converter clutch (PEMCC) operation. If the turbine acceleration is out of range during the FEMCC to PEMCC transition, a counter is incremented. When the count is 20 or more, the trouble code is set. This code does not cause the code is set, FEMCC to PEMCC operation before the A/C clutch engagement will be disabled.

PROBABLE CAUSE
- Degraded fluid
- Wheels severely out of alignment
- Internal transaxle problem

SERVICE PROCEDURE
- Check the transmission fluid.

If OK then:

- Internal transaxle failure