• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
The following fault table will help determine if a hydraulic circuit or an incorrect position of a valve train component affects the transmission operation.
Component | Cause | DTCs | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Automatic Transmission Fluid Filter Assembly | Oil filter loose or damaged | P0796 | ||||||||||||||
Control Solenoid (w/body and TCM) Valve Assembly |
| P0796 P0797 | ||||||||||||||
Lower Control Valve Body Assembly | Clutch select valve stuck off - debris, sediment, binding or scored bore | P0796 P0797 | ||||||||||||||
Fluid Pump Cover Assembly |
| P0796 | ||||||||||||||
1-2-3-4 and 3-5-R Clutch Housing Assembly | 1-2-3-4 clutch backing plate retaining ring not seated, causing the piston to over-travel and cut 1-2-3-4 clutch piston seal | P0796 | ||||||||||||||
4-5-6 Clutch Housing | 4-5-6 housing broken hub weld | P0796 |
Gear | 1-2-3-4 CL PC SOL 5 | 2-6 CL PC SOL 4 | 3-5 REV CL PC SOL 2 | LOW REV 4-5-6 CL PC SOL 3 |
---|---|---|---|---|
Park | OFF | OFF | OFF | ON |
Reverse | OFF | OFF | ON | ON |
Neutral | OFF | OFF | OFF | ON |
1st Braking | ON | OFF | OFF | ON |
1st | ON | OFF | OFF | OFF |
2nd | ON | ON | OFF | OFF |
3rd | ON | OFF | ON | OFF |
4th | ON | OFF | OFF | ON |
5th | OFF | OFF | ON | ON |
6th | OFF | ON | OFF | ON |
The clutch pressure control (PC) solenoid 3 is integral to the control solenoid (w/body and TCM) valve assembly and has no serviceable parts. The PC solenoid 3 is a normally high-pressure control solenoid which provides fluid pressure to the BR1 and 456 clutch regulator valve. The TCM controls the solenoid pressure by regulating the exhaust fluid. When the TCM commands the solenoid off, the exhausting fluid is stopped and the BR1 and 456 pressure is high. When commanded on, the clutch PC solenoid 3 regulates the amount of exhausting transmission fluid. Solenoid power is supplied by the TCM through a high side driver (HSD). The HSD protects the circuits and components that the TCM powers. Should the circuit overload the driver will shutdown. After the overload is removed the HSD reset.
• | No DTCs P0716 or P0717. |
• | No DTCs P0722 or P0723. |
• | No DTCs P1825 or P1915. |
• | The transmission input shaft speed is greater than 60 RPM. |
• | Low and reverse/4-5-6 clutch is commanded ON. |
• | The transmission output shaft speed is greater than 200 RPM. |
• | Low and reverse/4-5-6 clutch is commanded OFF. |
The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the low and reverse/4-5-6 clutch is commanded OFF for 0.5 seconds and the transmission input shaft speed is greater than 75 RPM from the anticipated input shaft speed.
The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the low and reverse/4-5-6 clutch is commanded ON for 0.5 seconds and the transmission input shaft speed is greater than 40 RPM from the anticipated input shaft speed.
• | DTCs P0796 and P0797 are Type A DTCs. |
• | The TCM commands maximum line pressure. |
• | The TCM inhibits TCC. |
• | The TCM freezes transmission adaptive functions. |
DTCs P0796 and P0797 are Type A DTCs.
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions.
Transmission Component and System Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
• | DT-47825 Control Solenoid Test Plate |
• | DT-47825-10 Jumper Harness |
Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records.
⇒ | If the DTC resets, go to Circuit/System Testing. |
⇒ | If the pressure is out of specification, correct this concern first. |
⇒ | If the DTC resets, continue on with testing. |
⇒ | If a concern is found, repair or replace the control solenoid (w/body and TCM) valve assembly. |
⇒ | If the solenoid is found to be leaking or stuck closed, replace the control solenoid (w/body and TCM) valve assembly. |
⇒ | If a concern if found in the valve body, repair or replace the valve body as necessary. |
⇒ | If a concern is found in the low and reverse/4-5-6 clutch assembly, repair or replace as necessary. |
Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .
Exercise | Normal Operation | Stuck OFF | Stuck ON |
---|---|---|---|
Steady State Gears 1st Braking 4, 5, 6 | 1st Braking, 4, 5, 6 | 1st Free Wheel, Neutral | 1st Braking, 4, 5, 6 |
Steady State Gears, 1 Free Wheel 2, 3 | 1st Free Wheel, 2, 3 | 1st Free Wheel, 2, 3 | 1st Braking, 4, 5, 6 |
Garage Shift | Park/Neutral to Reverse/Drive | Neutral 1st Free Wheel | Drive Gear |
Downshift from gears 4, 5, 6 to 1, 2, 3 | 1st Free Wheel, 2, 3 | 1st Free Wheel, 2, 3 | 1st Braking, 4, 5, 6 |
Upshift from gears 1, 2, 3 to 4, 5, 6 | 4, 5, 6 | Neutral | 4, 5, 6 |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control valve body replacement. Refer to Control Valve Lower Body and Upper Body Replacement . |
• | Low and reverse/4-5-6 clutch assembly repair or replace. Refer to Low and Reverse Clutch Overhaul and 4-5-6 Clutch Overhaul . |
• | Control solenoid (w/body and TCM) valve assembly replacement. Refer to Control Module References for replacement, setup, and programming. |
• | Perform the Service Fast Learn Adapts if internal transmission repairs are performed. |