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| • | 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 torque converter clutch (TCC) pressure control (PC) solenoid is part of the control solenoid valve assembly which has no serviceable components. The TCC PC solenoid is a normally low pressure control solenoid. The TCC PC solenoid regulates transmission fluid pressure to the TCC regulator valve in the lower valve body and the TCC control valve in the fluid pump assembly. When vehicle operating conditions are appropriate to apply the torque converter clutch, the transmission control module (TCM) will increase TCC PC current flow (duty cycle) thereby increasing pressure to move the TCC control valve into the apply position. When the TCC is fully applied, the engine is coupled directly to the transmission. TCC release is accomplished by the TCM decreasing current flow, dropping the apply pressure thereby allowing the TCC control valve to move to the release position. The TCM calculates torque converter slip speed based on the RPM signal from the input speed sensor (ISS) and engine RPM provided by the engine control module (ECM).
| • | DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0716, P0717, P0722, P0723, P0741, P0742, P2763, or P2764 is not set. |
| • | The engine speed is greater than 400 RPM for 5 seconds. |
| • | The ignition voltage is 9.0 volts or greater. |
| • | The transmission fluid temperature (TFT) is between -7 to +130°C (19-266°F). |
| • | The throttle position is 8 percent or greater. |
| • | The engine torque is 50 N·m (36 lb ft) or greater. |
| • | The 2nd gear ratio is between 2.75-3.17. |
| • | The 3rd gear ratio is between 1.78-2.04. |
| • | The 4th gear ratio is between 1.35-1.55. |
| • | The 5th gear is between 0.93-1.07. |
| • | The 6th gear is between 0.70-0.80. |
| • | The TCC is commanded ON. |
| • | The engine torque signal is valid. |
| • | The throttle position signal is valid. |
| • | DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0716, P0717, P0722, P0723, P0741, P0742, P2763, or P2764 is not set. |
| • | The engine speed is greater than 400 RPM for 5 seconds. |
| • | The ignition voltage is 9.0 volts or greater. |
| • | The TFT is 20-130°C (68-266°F). |
| • | The calculated throttle position is greater than 8 percent. |
| • | The engine torque is greater than 80 N·m (59 lb ft). |
| • | The vehicle speed greater than 16 km/h (10 mph). |
| • | Commanded gear is 2nd or greater. |
| • | The gear ratio is between 0.69-1.97. |
| • | Solenoid A is enabled. |
The TCM detects TCC slip greater than 150 RPM for 5 seconds with a TCC commanded ON pressure of 500 kPa or greater. This must occur 6 times during the same ignition cycle.
The TCM detects the TCC slip is between -20 and +30 RPM for 1.2 seconds or greater when the TCC is commanded OFF 5 times during the same ignition cycle.
| • | DTC P0741 is a Type B DTC. |
| • | The TCM inhibits top gear. |
| • | The TCM initiates the Hot Mode shift pattern. |
| • | The TCM commands the TCC OFF. |
| • | DTC P0742 is a Type A DTC. |
| • | The TCM initiates Hot Mode shift pattern. |
| • | The TCM freezes transmission adaptive functions. |
| • | The TCM commands the TCC ON. |
DTC P0741 is a Type B DTC.
DTC P0742 is a Type A DTC.
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions. Ensure the transmission fluid level is correct and there are no leaks.
Automatic Transmission Controls Schematics
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
Note: Perform a scan tool snapshot during the road test.
| • | Engine Speed |
| • | Engine Coolant Temperature |
| • | Transmission ISS |
| • | Transmission OSS |
| • | Transmission Fluid Temperature |
| • | Brake Pedal Switch |
| • | TCC Pressure Control Solenoid Valve Pressure Command |
| • | TCC Slip Speed |
| ⇒ | If not within the specified ranges, refer to Fluid Pressure High or Low . |
| ⇒ | If the Q8 control solenoid valve assembly does not pass the test, replace the Q8 control solenoid valve assembly. |
DTCs | Component | Condition | ||||||
|---|---|---|---|---|---|---|---|---|
P0741 P0742 | Upper Valve Body | TCC Control Valve
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P0741 P0742 | Upper Valve Body | TCC Regulator Valve
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P0741 P0742 | Q8 Control Solenoid Valve Assembly | TCC Pressure Control Solenoid
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P0741 | Torque Converter |
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P0741 | Support | Damaged seal | ||||||
P0741 P0742 | A/Transfer case Cover (403) | Release Blow-off
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P0741 | Upper Valve Body | Release exhaust port/orifice plugged or blocked | ||||||
P0741 | Turbine Shaft | Turbine shaft O-ring seal cut or damaged |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| Note: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection . |
| • | Refer to Control Module References for control solenoid valve assembly replacement, set-up, and programming. |
| • | Perform the Transmission Adaptive Values Learn following all transmission related repairs. |
| • | Perform the Torque Converter Removal and the Torque Converter Installation . |
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