Circuit/System Testing

NOTE:

You must perform the Circuit/System Verification first.

1. Engine idling at the normal operating temperature
2. Verify the transmission line pressures are within the specified range. Refer to Line Pressure Check , and Solenoid Valve Pressure .
   • If the pressures are not within range 

     Refer to Fluid Pressure High or Low .

   • Go to next step: If the pressures are within range 
3. Ignition OFF, remove the Q8 Control Solenoid Valve Assembly.
4. Verify the pressure changes for all solenoids when performing the solenoid test. Refer to Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test .
   • If the pressure does not change 

     Replace the Q8 Control Solenoid Valve Assembly.

   • Go to next step: If the pressure changes 
5. Verify the mechanical conditions listed below do not exist. Repair or replace as necessary.

DTC P0776 or P0777 - Upper Control Valve Body Assembly 

3-5-R regulator valve stuck/sticking - debris, binding, damaged valve, or scored bore.

DTC P0776 or P0777 - Lower Control Valve Body Assembly

• Actuator feed limit circuit supply fluid to solenoid restricted from debris, a stuck limit valve or sediment blockage.
• 3-5-R clutch boost valve - binding or scored bore - can cause harsh shifts.

DTC P0776 or P0777 - Q8 Control Solenoid Valve Assembly

• Clutch pressure control solenoid 2 stuck ON or stuck OFF.
• Control solenoid valve filter plate assembly, blocked or damaged gasket seal.

DTC P0776 - Channel Plate and Spacer Plate 

Oil channels or orifices blocked by debris.

DTC P0776 or P0777 - Transmission Fluid Pump

• Fluid pump housing vanes/rotor/slide damaged/scored.
• Transmission pump fluid outlet seal assembly damaged/leaking.

DTC P0776 - Transmission Cooling/Lubrication

• Oil filter or filter seal loose, plugged, or damaged.
• Restriction/leak in oil to air cooler/radiator.
• Restricted/leaking/kinked/damaged transmission oil cooler lines.
• Restriction/leak in transmission fluid pump assembly.

DTC P0776 - Torque Converter Assembly 

Torque converter overstressed due to high temperature, fluid boiled out.

DTC P0776 - 4-5-6 and 3-5-R Clutch Housing Assembly

• 3-5-R clutch backing plate retaining ring not seated or wave plate broken.
• 3-5-R piston seal torn, cut, or rolled.
• 4-5-6 and 3-5-R clutch housing assembly inner/outer seal damaged or dam pressure too high.

DTC P0776 or P0777 - Automatic Transmission Case Cover 

Blow off regulator ball stuck.

DTC P0776 or P0777 

3-5-R and 4-5-6 clutch fluid seal rings damaged, worn, or leaking.