P0773 on Lexus: How to Diagnose & Fix
Shift Solenoid "E" Electrical
1 Lexus model · 1 documented issue · 1 critical · $2,800-$5,000 repair
P0773 on Lexus by model: symptoms, diagnosis and fix
Early first-generation RX300 models are well known for premature automatic transmission failure, especially on AWD vehicles but also on FWD examples. Owners report delayed engagement into Drive or Reverse, harsh shifting, slipping on acceleration, and eventual loss of movement; teardown reports commonly cite burned clutches and damaged planetary gear components. The issue is widely documented in owner communities, repair databases, and NHTSA complaints, and is often attributed to a transmission that runs hot and is heavily stressed by vehicle weight.
Common Symptoms
- Delayed engagement into Drive or Reverse
- Harsh 1-2 or 2-3 shifts
- Transmission slipping under load
- Engine revs increase with little vehicle movement
- Burnt transmission fluid smell
- Vehicle eventually will not move
How to Fix
Diagnosis usually starts with checking fluid condition, line pressure behavior, and whether engagement delay or flare shifts are present when warm. In most cases, fluid changes do not cure an already failing unit; the durable fix is a quality rebuild or replacement transmission, often with updated hard parts and careful inspection of the cooler and valve body. Many owners also add an auxiliary transmission cooler after replacement to reduce repeat failures.
Owner tips & cautions
- TipIf replacing the transmission, owners commonly recommend installing an external transmission cooler and fully flushing cooler lines to avoid contaminating the rebuilt unit.
- TipUse Toyota Type T-IV compatible fluid and avoid generic fluid mixes on these early Aisin units.
Sources for this issue (1)
P0773 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0773 mean on a Lexus?
P0773 stands for "Shift Solenoid "E" Electrical." This code indicates the transmission control module detected an electrical problem in the circuit for shift solenoid E, such as an out-of-range current or voltage. Shift solenoids electronically route transmission fluid to engage gears, so an electrical fault can disrupt shifting. The vehicle may shift harshly, get stuck in a gear, or enter a limp/failsafe mode. The issue is electrical (wiring or the solenoid coil) rather than purely mechanical. On Lexus it is documented across 1 model: RX.
What are the most common causes of P0773?
The most common causes of P0773 are: Failed shift solenoid E (open or shorted coil), Damaged or corroded wiring or connector, Short to power or ground in the solenoid circuit, Low or contaminated transmission fluid affecting the solenoid, Internal transmission harness fault, Faulty transmission control module (less common). The specific cause varies by vehicle.
How much does it cost to fix P0773 on a Lexus?
Published repair estimates on Lexus range from $2,800 to $5,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0773 on a different make?
View P0773 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.