P1887

P1887 WITH 4 SPEED AUTOMATIC

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

The Torque Converter Clutch (TCC) release switch is part of the Automatic Transmission Fluid Pressure Manual Valve Position Switch (TFP Val. Position Sw.). The TFP Val. Position Sw. is mounted to the transmission valve body. The switch is normally-closed.

The switch signals the Powertrain Control Module (PCM) that the TCC is released. This is accomplished by Torque Converter release fluid pressure acting on the switch contact, thus opening the switch. When the voltage is high on the circuit, the Powertrain Control Module recognizes that the TCC is no longer engaged.

When the PCM determines that the TCC release switch is open (indicating that the TCC is not applied) and the TCC slip speed indicates that the TCC is applied, then DTC P1887 sets. DTC P1887 is a type A DTC.

CONDITIONS FOR SETTING THE DTC

^ No TCC Solenoid DTC P0741 or P0742

^ No Input Speed Sensor DTC P0716 or P0717

^ The engine is running.

^ The TFP Val. Position Sw. indicates D4 range.

^ The TCC is commanded ON.

^ The TCC slip speed is -20 to +20 RPM.

^ The TCC release switch is open.

^ All of the above conditions are met for 10 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM illuminates the Malfunction Indicator Lamp (MIL).

^ The PCM freezes shift adapts from being updated.

^ The PCM inhibits TCC engagement.

^ DTC P1887 is stored in the PCM history.

CONDITIONS FOR CLEARING THE MIL/DTC

^ The PCM turns OFF the MIL after three consecutive ignition cycles without a failure reported.

^ A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.

^ The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM.

DIAGNOSTIC AIDS

^ Inspect the wiring for poor electrical connections at the PCM. Inspect the wiring for poor electrical connections at the transmission 20-way connector. Look for the following conditions:

- A bent terminal

- A backed out terminal

- A damaged terminal

- Poor terminal tension

- A chafed wire

- A broken wire inside the insulation

^ When diagnosing for an intermittent short or open condition massage the wiring harness while watching the test equipment for a change.

TEST DESCRIPTION

The numbers below refer to the Step numbers on the diagnostic table.

4. This Step tests the PCM's ability to recognize an open circuit.

5. This Step tests the PCM's ability to recognize a grounded circuit.