P0745: Pressure control solenoid A electrical or stuck-off fault
Pressure control solenoid A malfunction
Severity: Inspect soon
Kelley Blue Book calls P0745 very serious and says to tow the car to a shop, so it should be inspected promptly.
It gets more serious if:
- Stop: Stop driving and have the car towed if the transmission slips, will not shift, overheats or will not engage a gear. Kelley Blue Book says not to drive with P0745.
P0745 in short
P0745 means the computer has found a fault in pressure control solenoid A, which sets hydraulic pressure in the transmission. A faulty solenoid or valve body, wiring, or debris in dirty fluid are the usual causes. Lexus has a software update on the 2019 RX350. Kelley Blue Book says do not drive it; get it towed.
A pressure control solenoid turns the computer's command into hydraulic pressure that applies clutches and sets shift feel. P0745 sets when the computer cannot read the right voltage from solenoid A, or finds the solenoid faulty even though the signal looks right.
Kelley Blue Book lists a defective valve body or solenoid, faulty wiring, a dirty transmission blocking oil passages, and debris in the solenoid. Slipping, overheating, poor fuel economy and trouble shifting follow.
Lexus bulletin L-SB-0005-19 shows that a software fix exists for some vehicles: on the 2019 RX350 the engine computer logic was updated for P0745-7F and harsh engagement into Drive.
Most likely causes
Cause 1: Faulty pressure solenoid or valve body
Common general cause- Why it ranks here
- Kelley Blue Book lists a defective valve body or pressure solenoid first.
- What would change this
- Rises if the solenoid fails resistance and pressure tests. Falls if it tests normal.
Cause 2: Faulty wiring
Common general cause- Why it ranks here
- Kelley Blue Book lists wiring faults and has the technician check continuity and reference voltage.
- What would change this
- Rises if continuity or voltage is out of range. Falls if the circuit tests good.
Cause 3: Dirty fluid or debris blocking passages
Common general cause- Why it ranks here
- Kelley Blue Book lists a dirty transmission blocking hydraulic passages and debris in the solenoid, and says fluid should be clear red.
- What would change this
- Rises if fluid is brown, burnt or has debris. Falls if clean.
Cause 4: Engine computer software (2019 Lexus RX350)
Supported by vehicle data- Why it ranks here
- Lexus L-SB-0005-19 updates the engine computer logic for P0745-7F and harsh engagement into Drive.
- What would change this
- Rises on a 2019 RX350. Falls on other vehicles.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Read all stored codes and freeze-frame data with a scan tool.
IfP0745 only, on a 2019 Lexus RX350 with harsh engagement into Drive
It meansAsk about the software update.
IfOther transmission codes are stored too
It meansWork on those with P0745.
Step 2: Ask a dealer whether your VIN has a bulletin or software update for P0745.
IfAn update applies
It meansDo the update first.
IfNo update applies
It meansLook at fluid and wiring.
Step 3: Have a shop check fluid color, solenoid wiring continuity and reference voltage, and the solenoid pressure with a gauge.
Warning:Pressure testing needs the car on a lift or with gauges plumbed into the transmission; leave it to a shop.
IfFluid is brown, burnt or has debris
It meansDebris may be blocking the solenoid.
IfWiring voltage or continuity is out of range
It meansRepair the circuit.
IfWiring is good but pressure is wrong
It meansThe solenoid or valve body is suspect.
Symptoms
- Slipping or harsh gear changes
- Check engine light
- Transmission overheating, or will not shift or engage Gets more serious: stop and have it checked.
- Poor fuel economy
How to fix
Step 1: Ask a dealer whether your VIN has an open bulletin or software update for P0745.
On your vehicle
LexusYour car
2019 · RX
Supported by vehicle dataLexus L-SB-0005-19 covers MIL with P0745-7F (pressure control solenoid A actuator stuck off) and harsh engagement into Drive on the 2019 RX350, fixed with an engine computer update. Whether the bulletin is still current is not verified.
L-SB-0005-19Status unverified
RX350 MIL with P0745 and harsh engagement into Drive
2019rx · NHTSA 10154804
Engine computer logic updated to prevent the condition. Only the NHTSA summary was read.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Related codes
Sources and review
- P0745 OBD-II Trouble Code: Pressure Control Solenoid A
- Lexus L-SB-0005-19: 2019 RX350 MIL with P0745 and harsh engagement into Drive
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error