P0945
PowertrainTransmission Pressurehigh severityHydraulic Pump Relay Circuit/Open
What P0945 Means
The control circuit for the transmission hydraulic pump relay is open or malfunctioning. The PCM cannot properly control the hydraulic pump through the relay.
Symptoms
- Transmission slipping or no drive
- Transmission warning light on
- Harsh or delayed engagement
Common Causes
- Faulty hydraulic pump relay
- Open or broken wiring in relay circuit
- Corroded connector
- Faulty PCM/TCM
Diagnostic Steps
- Inspect pump relay and connector
- Check relay circuit wiring for opens
- Test relay operation and coil resistance
- Verify PCM control signal to relay
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Budget handheld~$40
ANCEL AD410 →
No-phone-needed handheld — reads, clears, live data, freeze frame.
✓ ANCEL official store
Serious DIY~$100
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
SHOP FAVORITEShop-grade tablet~$300
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
✓ Autel official store
Pro diagnostics$1,500+
Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Community Confirmed Fixes
No confirmed fixes yet for this code. Be the first to contribute!
Submit a FixFound a Fix for P0945?
Help other technicians by sharing what worked on your vehicle.
Submit Your Fix