DESCRIPTION & OPERATION
Note. For additional information on transaxle operation, see appropriate OVERHAUL article.
Test Description
The numbers listed below refer to step numbers in the diagnostic procedure
- 1 - Determines if the scan tool is receiving power through the DLC.
- 2 - MIL should illuminate whenever the ignition is on and the engine is not running.
- 3 - Determines if the PCM is transmitting class 2 serial data to the DLC, and that the Class 2 data circuit is not open or shorted.
- 4 - Determines if a DTC is current or stored in history.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step tests the ability of the AT OSS to produce an AC voltage. This step also verifies the integrity of the wiring to the PCM.
- 4 - This step tests the AT OSS circuit for correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 5 - Disconnecting the TR switch, the ground path for all TR switch circuits would be removed and the PCM should recognize all circuits as open. The scan tool should display HI for all range signals.
- 6 - Tests the TR switch wiring for an open or lack of signal voltage from the PCM.
- 7 - Tests the TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal A should change to LOW.
- 8 - Tests the TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal B should change to LOW.
- 9 - Tests the TR switch wiring and the PCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal C should change to LOW.
The numbers listed below refer to step numbers in the diagnostic procedure
- 5 - Tests for an intermittent short or open condition in the engine wiring harness. The test light is used as a resistor in the circuit.
- 6 - Determines if the PCM or the TFT sensor is causing a steady, unchanging TFT reading.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - Tests the ability of the PCM to detect an open circuit.
- 5 - Tests the TFT sensor for correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 5 - Tests the TFT sensor signal circuit for being shorted to another circuit within the transmission. If the TFT sensor signal circuit shorts to another circuit, which is carrying voltage greater than five volts, the TFT sensor would become open.
- 6 - Tests the TFT sensor signal circuit for being shorted to voltage, which would be the cause for the open in the TFT sensor.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - Tests the ISS for correct resistance.
- 8 - Tests the ISS high signal circuit for being shorted to another circuit within the transmission.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - Tests the ISS for correct resistance.
- 8 - Tests the ISS high signal circuit for being shorted to another circuit within the transmission.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - Disconnecting the brake switch connector, jumping the circuit, and observing a status change, isolates the brake switch as the source of the DTC.
- 3 - If the ignition 3 voltage circuit shorts to ground, the CRUISE fuse opens.
- 5 - If the brake switch is properly adjusted, then the brake switch must be replaced.
- 8 - Replace the PCM only after you have completed the preceding diagnostic steps.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - Disconnecting the brake switch connector, and observing a status change, isolates the brake switch as the source of the DTC.
- 3 - This step inspects the signal circuit for a short to voltage, if the brake switch status on the scan tool did not change in Step 2.
- 4 - If the brake switch is properly adjusted, then the brake switch must be replaced.
- 5 - Replace the PCM only after you have completed the preceding diagnostic steps.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - Tests for low fluid level, which may cause slipping, and result in an incorrect gear ratio.
- 4 - Verifies that the correct gear ratios occur for commanded gears.
- 5 - Tests for low line pressure.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - Step inspects the transmission fluid to ensure that it is at the proper level.
- 3 - Step verifies that the TCC engages when commanded ON by the scan tool.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - Tests for a TCC release switch status change when the engine is running. If TCC release oil present, the switch should be open.
- 3 - This step tests for a TCC release switch status change when the engine is running. If TCC release oil is present, the switch should be open.
- 6 - This step ensures that the TCC release switch is in good working condition.
- 7 - This step tests the TCC circuit for a mechanical or hydraulic condition.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - This step verifies the ability of the PCM to command the PC solenoid valve.
- 3 - This step verifies that the automatic transmission wiring harness and the PC solenoid valve have correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step verifies a 2-2-3-3 shift pattern.
- 4 - This step tests for a mechanical or hydraulic condition causing the 1-2 SS valve to be stuck OFF, or the circuit to be released.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step verifies a 1-1-4-4 shift pattern.
- 4 - This step tests for a mechanical or hydraulic condition causing the 1-2 SS valve to be stuck ON, or the circuit to be applied.
The numbers listed below refer to step numbers in the diagnostic procedure
- 8 - This step tests the electrical operation of the solenoid.
- 9 - This step tests the PCM and the wiring to the transmission.
- 17 - This step verifies that the circuit has the correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step verifies a 4-3-3-4 shift pattern.
- 4 - This step tests for a mechanical or hydraulic condition causing the 2-3 SS valve to be stuck ON, or the circuit to be applied.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step verifies a 1-2-2-1 shift pattern.
- 5 - This step tests for a mechanical or hydraulic condition causing the 2-3 SS valve to be stuck OFF, or the circuit to be applied.
The numbers listed below refer to step numbers in the diagnostic procedure
- 8 - This step tests the electrical operation of the solenoid.
- 9 - This step verifies the ability of the PCM to command the solenoid.
- 17 - This step verifies that the circuit has the correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step tests the indicated range signal to the manual valve range actually selected.
- 6 - This step tests for correct voltage from the PCM.
The numbers listed below refer to step numbers in the diagnostic procedure
- 2 - This step tests for low fluid level, which can cause long shifts.
- 4 - This step tests for low line pressure, which can cause long shifts.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step tests the indicated range signal to the manual valve range actually selected.
- 6 - This step tests for correct voltage from the PCM.
The numbers listed below refer to step numbers in the diagnostic procedure
- 11 - This step tests the PCM and the wiring to the AT in-line 20-way connector.
- 14 - This step tests the control circuit for a short to voltage.
- 16 - This step tests the circuit for correct resistance.
The numbers listed below refer to step numbers in the diagnostic procedure
- 3 - This step tests the ability of the PCM to recognize a grounded circuit.
- 7 - This step tests for a mechanical or hydraulic condition.