Pinpoint Test F: Torque Converter Clutch (TCC), Line Pressure Control (LPC) Solenoids
- Refer to TRANSMISSION CONTROLS - 8F35
for schematic and connector information.
Normal Operation and Fault Conditions
When the electrical connector or solenoid is disconnected, inspect the connector for terminal condition, corrosion and contamination and the connector seal for damage. Clean, repair or install new components as required. If the power circuit to the transmission solenoids fails open, then all solenoids are failed electrically off. Check for an open, short to ground or the transmission connector disconnected. The TCC is controlled by a directly proportional solenoid. Like the shift solenoids the TCC solenoid is controlled by a "smart driver" capable of detecting open, short to ground and short to power faults. In the event of an open circuit or short to power fault the TCC circuit is failed open. The TCC and LPC solenoids share a high side driver. Anytime power is removed from the transmission, the TCC solenoid defaults to MAX line pressure with open TCC. LPC is controlled by an inversely proportional solenoid (0 current = max pressure, max current = min line pressure). The LPC solenoid is controlled by a "smart driver" capable of detecting open, short to ground or short to power faults. Power is supplied to both solenoids by the transmission solenoid power control 1 (TSPC1).
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P0740:00 Torque Converter Clutch Solenoid Circuit/Open: No Sub Type Information Open circuit in the TCC solenoid or wiring harness. PCM P0743:00 Torque Converter Clutch Solenoid Circuit Electrical: No Sub Type Information Open or short to ground in the TCC solenoid or wiring harness. PCM P0748:00 Pressure Control Solenoid "A" Electrical: No Sub Type Information LPC solenoid electrical circuit general fault. May set along with DTC P0960, P0962 and P0963. PCM P0960:00 Pressure Control Solenoid "A" Control Circuit/Open: No Sub Type Information Open circuit in LPC solenoid or solenoid circuitry. PCM P0961:00 Pressure Control Solenoid "A" Control Circuit Range/Performance: No Sub Type Information Intermittent short to ground in LPC solenoid or solenoid circuitry. PCM P0962:00 Pressure Control Solenoid "A" Control Circuit Low: No Sub Type Information Short to ground in LPC solenoid or solenoid circuitry. PCM P0963:00 Pressure Control Solenoid "A" Control Circuit High: No Sub Type Information Short to power in LPC solenoid circuitry. PCM P2669:00 Actuator Supply Voltage "B" Circuit/Open: No Sub Type Information TSPC2 supplies voltage to the TCC and LPC solenoids. This DTC indicates that the TSPC2 is not supplying power to the solenoids. May be caused by wiring or connector issue, or PCM failure. May cause loss of fuel economy due to no TCC operation. PCM P2760:00 Torque Converter Clutch Pressure Control Solenoid Intermittent: No Sub Type Information Intermittent circuit in the TCC solenoid or wiring harness. Open, short to ground or short to power. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- TCC and LPC solenoid(s)
- Transmission internal wiring harness
- PCM
- F1 CHECK THE SOLENOID POWER CIRCUIT TSPC1 FOR VOLTAGE
- Ignition OFF.
- Disconnect: Transmission Harness C1520.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C1520-14 Ground
Is the voltage greater than 11 volts?
Yes GO to F4 No GO to F2 - F2 CHECK THE TSPC1 SOLENOID POWER CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: PCM C1915E.
- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.
Is the resistance less than 3 ohms?
Yes GO to F3 No REPAIR the transmission vehicle harness circuit. - F3 CHECK THE TSPC1 SOLENOID POWER CIRCUIT FOR SHORT TO GROUND
- Measure:
Positive Lead Measurement / Action Negative Lead C1915E-92 Ground
Is the resistance greater than 10, 000 ohms?
Yes Verify all PCM power circuits and fuses. If no problem is found, Refer to PCM GUIDED ROUTINE TESTING
PROGRAM the PCM to the latest calibration level. PERFORM the Solenoid Body Strategy Data Download procedure. REFER to: Transmission Strategy Download .No REPAIR the transmission vehicle harness circuit. - Measure:
- F4 CHECK VEHICLE HARNESS SOLENOID CONTROL CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: PCM C1915E
- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.
- Measure the resistance of the solenoid control circuits using the following chart.
Positive Lead Measurement / Action Negative Lead C1915E-65 C1520-11 C1915E-64 C1520-13
Is the resistance less than 3 ohms on the suspect circuit?
Yes GO to F5 No REPAIR the transmission vehicle harness circuit. CLEAR the DTCs. - F5 CHECK VEHICLE HARNESS SOLENOID CONTROL CIRCUITS FOR A SHORT TO GROUND
Is the resistance greater than 10, 000 ohms on the suspect circuit?
Yes GO to F6 No REPAIR the transmission vehicle harness circuit. CLEAR the DTCs. - F6 CHECK SOLENOID CONTROL CIRCUITS FOR A SHORT TOGETHER WITH POWER CIRCUITS
- Measure:
TCC Solenoid
Positive Lead Measurement / Action Negative Lead C1915E-64 C1915E-19 C1915E-64 C1915E-80 C1915E-64 C1915E-70 C1915E-64 C1915E-91 C1915E-64 C1915E-92 C1915E-64 C1915E-93 C1915E-64 C1915E-71 C1915E-64 C1915E-95 C1915E-64 C1915E-29
- Measure:
LPC Solenoid
Positive Lead Measurement / Action Negative Lead C1915E-65 C1915E-19 C1915E-65 C1915E-80 C1915E-65 C1915E-70 C1915E-65 C1915E-91 C1915E-65 C1915E-92 C1915E-65 C1915E-93 C1915E-65 C1915E-71 C1915E-65 C1915E-95 C1915E-65 C1915E-29
Is the resistance greater than 10, 000 ohms on the suspect circuit?
Yes GO to F7 No REPAIR the transmission vehicle harness circuit. CLEAR the DTCs. - Measure:
- F7 CHECK TRANSMISSION INTERNAL WIRING HARNESS FOR AN OPEN CIRCUIT
- REMOVE the main control cover. REFER to: Main Control Cover .
- Measure:
TCC Solenoid
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 13C1841-2
- Measure:
LPC Solenoid
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 11C1840-2
- Measure:
TSPC1 Circuits
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 14C1841-1
Transmission Harness Connector, component side, pin 14C1840-1
Are the resistances less than 3 ohms?
Yes GO to F8 No INSTALL a new internal wiring harness. REFER to: Transmission Internal Wiring Harness Frame . - F8 CHECK TRANSMISSION INTERNAL WIRING HARNESS FOR A SHORT TO GROUND
- Measure:
TCC Solenoid
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 13Ground
- Measure:
LPC Solenoid
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 11Ground
- Measure:
TSPC1 Circuits
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 14Ground
Are the resistances greater than 10, 000 ohms?
Yes GO to F9 No INSTALL a new internal wiring harness. REFER to: Transmission Internal Wiring Harness Frame . - Measure:
- F9 CHECK SOLENOID RESISTANCE
- Measure and record the resistance of the suspected solenoid. REFER to: Solenoid .
Compare the recorded value with the chart below:
Solenoid Ohms LPC solenoid 4.6 to 5.2 TCC solenoid 4.6 to 5.2
Are the solenoid resistances within specification?
Yes All tests have passed, INSPECT the connector terminals for fitment or intermittent connections. No INSTALL a new solenoid for the solenoid that failed the resistance check. REFER to: Solenoid . - Measure and record the resistance of the suspected solenoid. REFER to: Solenoid .
Compare the recorded value with the chart below: