Meaning

The transmission control module has detected a general malfunction in the automatic transmission shift system. The monitoring circuit indicates that one or more shift operations are not completing correctly, without identifying a specific solenoid.

Common causes

• Insufficient overall transmission hydraulic pressure (pump wear, internal leaks)
• Low ATF level or degraded/contaminated transmission fluid
• One or more faulty or stuck shift solenoids
• Worn or damaged internal clutches or bands
• Faulty input/output speed sensor providing incorrect ratio readings
• Obstructed valve body or stuck valves

Symptoms

• Check engine or transmission warning light on
• Erratic, harsh, delayed, or absent gear shifts
• Transmission in limp mode
• Transmission slipping in multiple gears
• Transmission overheating

Severity

What to do

1. Check ATF level and condition; replace filter and fluid if necessary
2. Read all related fault codes to identify specific solenoids or sensors involved
3. Measure transmission hydraulic pressure under various operating conditions
4. Test shift solenoids individually with a multimeter and scan tool
5. Inspect the valve body and proceed with internal transmission overhaul if pressure is insufficient

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