Pressure Regulator Check (S/C to +12V)

DTC P0748
Pressure regulator check (S/C to +12V).

Possible causes by suggested order of priority:
- C193/53 (OLG) shorted to +12V.
- ECU fault.

C193/53 (OLG) shorted to +12V.
CHECK THE FOLLOWING:
- C193/53 (OLG) shorted to +12V..
- Disconnect EAT C193 before measuring voltage between C193/53 (OLG) and vehicle earth.
ACCEPTABLE RESULTS
- Between 0.0V and 4.0V.
DIAGNOSTIC HINTS
- If the voltage is above the acceptable range check the harness connected to C193/53 (OLG) for short circuit to +12V

ECU fault.
CHECK THE FOLLOWING:
- Ensure that the check for short to +12V has been carried out.
- Check transmission ECU by substitution with a known good unit.
POSSIBLE FAULTS
- Faulty transmission ECU.