P0748: Pressure Control Solenoid A Electrical
Severity: medium
What it means: The transmission computer sees an electrical problem with pressure control solenoid A, the valve that sets how firmly the transmission applies its clutches. Line pressure can end up too high (harsh shifts) or too low (slipping).
Safe to drive? Usually drivable carefully to a shop. The transmission may shift harshly or go into a backup mode.
Common symptoms
- Harsh or soft shifts
- Erratic shifting
- Check engine light
- Transmission stuck in one gear (backup mode) on some cars
Likely causes, ranked
- Faulty pressure control solenoidShop
- Wiring or connector problem at the transmissionShop
- Sediment in the valve bodyShop
Vehicle-specific notes
- 1998–2002 Oldsmobile Intrigue: On Edmunds, a 1999 Intrigue owner's dealer found P0748 during a harsh-shift episode and pointed to GM's bulletin to replace the side-mounted solenoids. Read the full answer · Source
What it means: The transmission computer sees an electrical problem with pressure control solenoid A, the valve that sets how firmly the transmission applies its clutches. Line pressure can end up too high (harsh shifts) or too low (slipping).
Severity: Medium. Safe to drive? Usually drivable carefully to a shop. The transmission may shift harshly or go into a backup mode.
DIY or shop?
Shop. Testing the solenoid circuit and line pressure needs a scan tool and a gauge.
Before you replace parts
- Read all stored codes and freeze-frame data.
- Check the transmission fluid level and condition.
- Have the solenoid circuit and connector tested before replacing parts.
- Check your VIN for transmission service bulletins.
Safety / mechanic note
Verify with a mechanic. Harsh shifting or slipping can cause a sudden loss of drive. A code points to a circuit or system, not always a specific part.