P0948Hydraulic Pump Relay/Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The control line of the hydraulic pump relay or driver shows a higher voltage than expected, typically because it is shorted to battery voltage or the relay coil is open on a low-side driver. The pump then cannot be switched on, or the module sees it as active when it is not. J2012 places this code with the pump control circuit; Ferrari however reads P0948 on its DCT as no signal from the system pressure output, an unrelated use. The pump and accumulator unit of an automated gearbox is described in a ZF patent. CARB requires circuit checks on transmission outputs. P0947 is the low counterpart, P0945 the open fault and P0946 the plausibility fault. Expect a warning and possible loss of pump pressure.
- What you may notice
- Warning light on
- Pump does not start
- Gear changes not possible or stop-start disabled
- Likely causes
- LikelyRelay control wire shorted to battery voltage
- PossibleOpen relay coil seen as high level by the driver
- RareControl module fault
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €30 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.