AutoCodes – Generic – P0788

P0788 Code - Shift/Timing Solenoid High

Quick Answer

Shift solenoid valve ST is switched ON OFF by a signal from Engine Control Module (ECM) so that let in or out timing of 2nd brake is adjusted by operating orifice control valve. Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty shifting solenoid valve. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0788 indicates Shift/Timing Solenoid High.
Common causes: Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty shifting solenoid valve.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 9,923

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 08, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0788 Description

Shift solenoid valve ST is switched ON OFF by a signal from Engine Control Module (ECM) so that let in or out timing of 2nd brake is adjusted by operating orifice control valve. Therefore, shift solenoid valve ST operates when letting in or out reverse clutch.

OBDII Code P0788 - Shift/Timing Solenoid High - AutoCodes.com — P0788 Code - Shift/Timing Solenoid High

What does this mean?

What are the Possible Causes of the DTC P0788?

Low transmission fluid level
Dirty transmission fluid
Faulty shifting solenoid valve
Shifting solenoid valve harness is open or shorted
Shifting solenoid valve circuit poor electrical connection

How to Fix the DTC P0788?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0788 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0788 code?

Need more information on how to fix the P0788 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0788 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P0788 Isuzu — 3-2 Shift Solenoid Control Circuit High Voltage
P0788 Lexus — Shift/Timing Solenoid High
P0788 Mercedes-Benz — Shift/Timing Solenoid High
P0788 Scion — Shift/Timing Solenoid High
P0788 Toyota — Shift/Timing Solenoid High

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.