Diagnostic Procedure
WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Steps 5- 9
require the vehicle be raised and supported and the oil pan be removed for access to the shift solenoids to be tested. See appropriate AUTOMATIC article in TRANSMISSION SERVICING.
NOTE:
Check the shift solenoid valve SL1 when DTC P0753 is output, check the shift solenoid valve SL2 when DTC P0758 is output, check the shift solenoid valve SL3 when DTC P0763 is output, check the shift solenoid valve S4 when DTC P0768 is output and check the shift solenoid valve SR when DTC P1818 is output.
- Warm the engine to normal operating temperature. Turn the ignition to the OFF position. Connect the scan tool to the DLC3 and turn the ignition switch to the ON position and turn ON the scan tool. Select the item SHIFT in the ACTIVE TEST and operate the shift solenoids on the scan tool. Operate the shift solenoid valve and set each shift position by yourself. Check each shift solenoid valve. Operate the vehicle at less than 31 MPH, while pressing the SHIFT UP and then the SHIFT DOWN buttons. If all shift solenoid valves operate correctly, replace the ECM. If not, go to next step.
- Disconnect the 2 transaxle wiring harness connectors from the transaxle. Then measure the resistance between the following terminals:
- SL1+ and SL1-
- SL2+ and SL2-
- SL3+ and SL3-
The specification is 5.0-5.6 ohms at 68°F (20°C). If all the tests were within specification, go to next step. If SL1+ to SL1- was out of specification, go to step 5. If SL2+ to SL2- was out of specification, go to step 6. If SL3+ to SL3- was out of specification, go to step 7.
- Measure the resistance between terminal S4 and ground. Then measure the resistance between terminal SR and ground. Specification is 11-15 ohms at 68°F (20°C). If S4 is not as specified, go to step 8. If SR is not as specified, go to step 9. If both checks were as specified, go to next step.
- Connect the 2 transaxle wiring harness connectors to the transaxle. Disconnect the appropriate ECM connector and measure the resistance between the following terminals:
- SL1+ to SL1- . Specification is 5.0-5.6 ohms at 68°F (20°C).
- SL2+ to SL2- . Specification is 5.0-5.6 ohms at 68°F (20°C).
- SL3+ to SL3- . Specification is 5.0-5.6 ohms at 68°F (20°C).
- S4 to E1. Specification is 11-15 ohms at 68°F (20°C).
- SR to E1. Specification is 11-15 ohms at 68°F (20°C).
If all measurements are within specification, replace ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. If any measurements are not within specification, replace the transaxle wiring harness and connector.
- Remove shift solenoid valve SL1 and measure the resistance between the terminals. Specification is 5.0-5.6 ohms at 68°F (20°C). Then using a wire from battery voltage, with a 21 watt bulb, to the No. 2 terminal and ground the No. 1 terminal. See Figure. The resistance test should be within specification and the solenoid should make an operating noise when voltage is applied. If the shift solenoid valve operated as specified, replace the transaxle wiring harness and connector. If the shift solenoid valve failed either test, replace the shift solenoid valve SL1.
- Remove shift solenoid valve SL2 and measure the resistance between the terminals (specification is 5.0-5.6 ohms at 68°F (20°C). Then using a wire from battery voltage, with a 21 watt bulb, to the No. 2 terminal and ground the No. 1 terminal. See Figure. The resistance test should be within specification and the solenoid should make an operating noise when voltage is applied. If the shift solenoid valve operated as specified, replace the transaxle wiring harness and connector. If the shift solenoid valve failed either test, replace the shift solenoid valve SL2.
- Remove shift solenoid valve SL3 and measure the resistance between the terminals (specification is 5.0-5.6 ohms at 68°F (20°C). Then using a wire from battery voltage, with a 21 watt bulb, to the No. 2 terminal and ground the No. 1 terminal. See Figure. The resistance test should be within specification and the solenoid should make an operating noise when voltage is applied. If the shift solenoid valve operated as specified, replace the transaxle wiring harness and connector. If the shift solenoid valve failed either test, replace the shift solenoid valve SL3.
- Remove the shift solenoid valve S4. Measure the resistance between the solenoid positive terminal and the solenoid body. The specification is 11-15 ohms at 68°F (20°C). Then using a wire from battery voltage to the No. 2 terminal and ground the No. 1 terminal. See Fig 3. The resistance test should be within specification and the solenoid should make an operating noise when voltage is applied. If the shift solenoid valve operated as specified, replace the transaxle wiring harness and connector. If it did not operate as specified, replace the shift solenoid valve S4.
- Remove the shift solenoid valve SR. Measure the resistance between the solenoid positive terminal and the solenoid body. The specification is 11-15 ohms at 68°F (20°C). Then using a wire from battery voltage to the No. 2 terminal and ground the No. 1 terminal. See Fig 2. The resistance test should be within specification and the solenoid should make an operating noise when voltage is applied. If the shift solenoid valve operated as specified, replace the transaxle wiring harness and connector. If it did not operate as specified, replace the shift solenoid valve SR.